ELECTROTYPING 


9^^  > 


ELECTROTYPING 


A   PRACTICAL  TREATISE  ON  THE  ART  OF  ELEC- 
TROTYPING  BY   THE   LATEST 
KNOWN    METHODS. 


CONTAINING  HISTORICAL  REVIEW  OF  THE  SUBJECT,   FULL 
DESCRIPTION    OF    THE    TOOLS    AND    MACHINERY 
REQUIRED,   AND    COMPLETE  INSTRUCTIONS 
FOR    OPERATING    AN    ELECTRO- 
TYPING    PLANT. 


BY  C.  S.  PARTRIDGE. 


SECOND   EDITION. 


CHICAGO: 

The  Inland  Printer  Company. 

1908. 


Copyright,   1899, 
Copyright,   1908, 

By  The  Inland  Printer  Company,  Chicago. 


PRESS    OF    THE    HENRY    O.    SHEPARD    COMPANY. 


PREFACE  TO  FIRST  EDITION. 

THE  art  of  electrotyping  has  within  recent  years  made 
material  advancement.  Labor-saving  machinery 
and  appliances  have  simpHfied  and  at  the  same  time 
insured  greater  accuracy  in  the  mechanical  features  of 
the  art,  while  the  constant  and  increasing  demand  for 
rapid  work  has  been  an  incentive  to  invention  and 
research,  with  the  result  that  electrotypes  are  now  pro- 
duced in  much  less  time  than  was  formerly  required. 
That  the  literature  of  electrotyping,  although  of  great 
value,  is  hardly  up  to  date,  is  evidenced  by  the  state- 
ments of  Urquhart,  Wilson,  Langbein  and  others,  to  the 
effect  that  from  seven  to  twenty  hours  are  required  to 
deposit  shells  of  practical  thickness.  While  these  state- 
ments were,  perhaps,  correct  at  the  time  they  were  pub- 
lished, they  can  hardly  be  considered  accurate  now,  in 
view  of  the  fact  that  the  plate  from  which  this  page  is 
printed  was  deposited  in  fifteen  minutes. 

In  the  following  pages,  revised  from  a  series  of  arti- 
cles in  The  Inlm%d  Printer,  I  have  endeavored  to 
describe,  as  clearly  and  simply  as  possible,  the  most 
approved  methods  of  producing  electrotypes,  with  the 
hope  that  the  information  may  prove  of  value  both  to 
the  professional  and  the  amateur, 

C.  S.  PARTRIDGE. 
Chicago,  June,  1899. 


PREFACE  TO  SECOND  EDITION. 

THE  general  favor  accorded  "Electrotyping-"  made 
several  printings  of  the  first  edition  necessary. 
This  second  edition  has  been  revised  and  corrected 
to  date  and  much  new  matter  added,  an  important 
addition  being  a  glossary  or  reference  list  of  terms, 
processes  and  apparatus. 

C.  S.  PARTRIDGE. 

Chicago,  December,  1908. 


*♦ 


CONTENTS 


CHAPTER  PAGE 

I.  Historical  Review        .        .                ...  7 

II.  The  Battery 18 

III.  The  Dynamo 25 

IV.  The  Bath           .                .        .        .     '  .        .  35 
V.  Steel,  Brass  and  Nickel  Baths        ...  41 

VI.  Management  of  Baths 46 

VII.  Agitation  of  Baths 51 

VIII.  Measuring   Instruments          ....  58 

IX.  Preparation  of  Work           ....  63 

X.  MoLniNG       . '67 

XI.  Building         '  .        .        .        .        .        .        .        .78 

XII.  Metallizing 83 

XIII.  The  Conductors 94 

XIV.  Depositing           99 

XV.  Casting            105 

XVI.  Finishing             119 

XVII.  Trimming  and  Routing 127 

XVIII.  Revising 136 

XIX.  Blocking 143 

XX.  Dr.  Albert's  Metal  Molds        .        .        .  150 

Reference  List  of  Terms,  Processes  and  Appa- 
ratus           161 


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ELECTROTYPING. 


CHAPTER    I. 

HISTORICAL    REVIEW. 

DURING  the  period  of  1837- 1839,  Professor  Jacobi, 
of  St.  Petersburg,  Mr.  Thomas  Spencer,  of  Liver- 
pool, and  Mr.  C.  J.  Jordan,  of  London,  made  at  differ- 
ent times  announcement  of  their  independent  discovery 
of  the  art  of  electrotyping.  According  to  one  author- 
ity the  rival  claims  of  Professor  Jacobi  and  Mr.  Spencer 
were  presented  by  them  in  person  before  the  Chemical 
Section  of  the  British  Association  for  the  promotion  of 
Science,  and  this  august  assembly  after  prolonged  dis- 
cussion decided  that  both  had  independently  arrived  at 
the  same  result,  but  that  the  priority  of  discovery  was 
undoubtedly  Mr.  Spencer's.  However,  this  decision  of 
the  society  with  the  high-sounding  title  did  not  by  any 
means  settle  the  controversy,  which  became  still  further 
complicated  by  the  later  claims  of  Mr.  Jordan,  In  view 
of  the  conflicting  character  of  the  evidence  we  are 
inclined  to  divide  the  honor  between  the  gentlemen 
named;  but  whatever  merit  may  attach  to  their  respec- 
tive claims  as  discoverers,  there  is  probably  no  question 
but  that  the  credit  for  the  first  practical  application  of 
the  new  art  to  the  printing  business  belongs  to  an  Amer- 


8  ELECTROTYPING. 

ican  —  Mr.  J.  A.  Adams,  of  New  York,  who  produced 
successful  electrotypes  of  wood  engravings  in  1841.  It 
is  to  American  inxentive  genius,  also,  that  we  are  in- 
debted for  most  of  the  labor-saving  methods  and  machin- 
ery which  have  brought  the  art  to  its  present  state  of 
perfection.  In  England,  electrotyping  seems  to  have 
been  first  utilized  chiefly  for  the  production  of  metallic 
art  work  such  as  engraved  medals,  statuary,  etc. 
Messrs.  Elkington  &  Co.  were  so  successful  in  this 
branch  of  the  art  that  in  1845  they  had  established  a 
considerable  business  in  the  duplication  of  cups,  vases 
and  other  articles,  deposited  entirely  in  gold,  silver  and 
copper.  While  our  friends  over  the  water  have  perhaps 
excelled  in  this  feature  of  electrotyping,  Americans  were 
quick  to  grasp  and  develop  the  possibilities  of  the  art 
as  applied  to  printing  purposes.  In  1863,  Mr.  William 
Filmer,  an  electrotyper  of  New  York,  who  had  much 
to  do  with  the  early  development  of  electrotyping,  after 
an  extended  trip  abroad  stated  that  electrotyping  as 
applied  to  the  printing  industry  was  generally  recognized 
in  Europe  as  an  American  art. 

The  discovery  of  electrotyping,  like  many  other 
important  discoveries,  was  purely  accidental.  Mr. 
Spencer,  for  instance,  was  trying  some  experiments  in 
electro-chemistry.  He  had  immersed  a  copper  plate 
in  a  solution  of  sulphate  of  copper  and  a  zinc  plate  in 
a  solution  of  common  salt,  connecting  them  together 
by  a  wire,  and  separating  the  fluids  by  a  partition  of 
plaster  of  paris.  In  order  that  no  action  should  take 
place  on  the  wire  connecting  the  plates,  he  covered  it 
with  sealing  wax,  and  in  so  doing,  spilled  some  of  the 
wax  on  the  copper  plate.     After  a  few  days  he  found 


ELECTROTYPING.  9 

that  copper  crystals  had  covered  the  copper  electrode 
except  the  portion  protected  by  the  drops  of  wax.  It 
at  once  occurred  to  him  that  by  the  application  of  wax 
or  other  non-conducting  substance,  he  could  perfectly 
control  the  deposition  of  the  metal.  Mr.  Spencer  then 
coated  a  plate  of  copper  with  beeswax,  and  scratched 
his  name  through  the  wax  on  the  plate  and  connected  it 
with  a  zinc  plate  of  corresponding  size,  immersing  them 
in  the  solutions  as  before.  After  a  few  hours  he  found, 
as  he  expected,  that  the  portion  of  the  plate  from  which 
the  wax  had  been  removed  was  coated  with  bright 
metal,  while  the  protected  portions  remained  untouched. 

The  discovery  of  electrotyping  created  hardly  less 
interest  than  the  nearly  contemporaneous  invention  of 
the  electric  telegraph.  Scientists,  professional  men  and 
workmen  became  alike  interested,  and  the  copying  of 
medals,  coins,  etc.,  by  electrotyping  becarne  a  popular 
amusement  of  the  time. 

The  apparatus  employed  at  this  time  consisted  of  a 
single  cell,  as  before  described.  The  back  of  the  coin 
or  medal  to  be  copied  was  first  coated  with  wax  or  var- 
nish. Copper  was  then  deposited  on  its  face  to  form  a 
matrix,  which,  after  having  been  removed  from  the  coin 
and  properly  prepared,  was  returned  to  the  bath  to 
receive  in  its  turn  a  deposit  of  copper  in  the  form  of 
a  facsimile  of  the  original. 

In  1840,  Mr.  Joseph  Murray  discovered  that  non- 
conductive  substances  could  be  made  conductive  by 
applying  to  them  a  film  of  graphite.  This  was  a  nota- 
ble step  in  the  progress  of  the  art,  for  it  not  only  made 
possible  the  duplication  of  nonmetallic  objects,  but 
opened  the  way  for  the  use  of  gutta-percha,  wax  and 


10  ELECTROTYPING. 

similar  substances  for  molding  material  in  which  an 
impression  of  the  coin  or  other  object  could  be  made, 
thereby  greatly  expediting  the  work  by  saving  the  lime 
required  to  make  a  matrix  in  copper. 

The  invention  of  the  separate  battery  about  the 
same  time,  by  Mr.  Mason,  marked  another  material 
advancement  in  the  art. 

Mr.  Adams  made  his  first  electrotype  copies  of 
wood  engravings  by  depositing  copper  directly  on  the 
engraving  and  using  the  deposit  for  a  matrix.  The 
process  was,  of  course,  very  crude  and  invariably 
destroyed  the  wood  engraving,  but  it  was  of  value  as 
an  insurance  against  checking  and  because  the  electro- 
type would  stand  much  more  wear  than  the  wood  cut. 

Mr.  J.  W.  Wilcox,  of  Boston,  Massachusetts,  an 
employee  of  Mr.  Daniel  Davis,  was  the  originator  of 
the  methods  by  which  electro^yping  was  made  of  prac- 
tical use  for  the  printing  business.  Mr.  Davis  had 
produced  a  few  electrotypes,  but  after  the  method  laid 
down  by  European  experimenters ;  and  it  may  be  that 
Mr.  Wilcox  obtained,  through  his  connection  with  Mr. 
Davis,  his  first  information  of  the  possibility  of  making 
duplicates  by  galvanoplasty,  yet  Mr.  Davis  did  not 
encourage,  but,  on  the  contrary,  endeavored  to  dis- 
suade Mr.  Wilcox  from  the  notion  that  something,  in 
a  business  way,  could  be  gotten  out  of  the  new  art. 
Mr.  Wilcox  had  so  much  faith  in  a  successful  result 
that  he  resigned  his  position,  that  of  foreman  for  Mr. 
Davis,  engaged  a  room  and  devoted  his  energies  to  the 
work.  In  less  than  one  month  thereafter  he  produced 
electrotypes  from  cuts  and  type,  without  injury  to  the 
originals,  by  virtually  the  same  manipulation  that  is 


ELECTROTYPING.  11 

now  used.  His  most  important  discovery  was  of  a 
wax  composition  in  which  molds  could  be  readily  made 
by  pressure.  He  immediately  started  in  the  business  of 
making  plates  for  printers'  use,  and  was  the  first  to 
make  a  business  of  electrotyping.  He  showed  speci- 
mens of  electrotypes  in  the  fifth  exhibition  of  the  Mas- 
sachusetts Charitable  Mechanic  Association  (1847), 
and  page  42  of  the  report  for  that  year  reads  as 
follows : 

2.  J.  W.  Wilcox,  Boston.  Specimens  of  Electrotype. 
These  specimens  are  produced,  as  we  think,  in  a  manner 
original  with  Mr.  Wilcox.  The  originality,  consists  in  making 
the  matrix,  upon  which  the  copper  is  deposited,  of  wax, 
either  coated  or  mingled  with  plumbago.  Previously,  matrices 
were  usually  made  of  soft  metal  upon  which,  in  a  melted 
state,  the  original  plate  was  laid  and  subjected  to  a  smart 
blow,  when  the  melted  metal  was  partially  hardened  in  the 
process  of  cooling.  Objections  to  this  mode  are:  liability  of 
injuring  molds  or  plates  made  of  soft  materials  and,  of 
course,  its  inapplicability  to  wood  engravings,  and  the  diffi- 
culty of  obtaining  perfect  matrices,  since  even  a  small  por- 
tion of  air  beneath  the  plate  might,  when  the  blow  is  given, 
materially  injure  the  cast.  Besides,  the  old  mode  is  hardly 
practicable,  when  the  plate  is  of  great  extent.  By  the 
method  of  Mr.  Wilcox,  matrices  of  any  dimensions  can  be 
made  from  a  plate  or  mold  of  any  materials  without  the 
least  injury  to  the  original ;  and  the  liability  of  failing  to 
obtain  a  good  matrix  is  almost  wholly  obviated. 

We  hence  infer  that,  among  other  benefits  resulting  from 
this  process,  it  will  be  found  more  economical,  and  will  con- 
tribute much  to  the  beauty  and  perfection  of  the  impression, 
to  use  copper  plates  made  from  the  blocks  for  wood  engra- 
vings, than  to  use  the  blocks  themselves.  Indeed,  several  of 
the  specimens  exhibited  were  of  this  kind,  and  impressions 
from  them  substantiate  the  opinion  of  the  committee. 

One  of  the  specimens  examined  was  a  copper  stereotype 


12  ELECTROTYPING. 

plate  for  common  printing,  accompanied  by  an  impression 
from  the  plate.  This  suggests  to  the  committee  what  they 
consider  the  most  important  feature  of  the  subject,  namely, 
the  probability  that  copper  stereotype  plates  will  take  the 
place  of  common  type-metal  plates.  The  circumstances  to 
warrant  this  probability  are,  the  greater  durability  of  copper 
plates  and  the  more  perfect  outline  of  the  letters.  That 
copper  plates  will  be  more  durable  does  not  admit  of  a 
doubt ;  and  some  practical  men  express  their  belief  that  they 
will  last  six  times  as  long  as  type-metal  plates.  If  so,  and 
if,  as  is  almost  certain,  copper  is  soon  to  become  much 
cheaper  than  at  present,  there  will  be  a  decided  economy  in 
using  copper  plates,  and  the  use  of  them  will  contribute  very 
materially  to  the  diffusion  of  knowledge,  and,  as  we  trust,  to 
the  growth  of  virtue.  In  addition  to  this,  the  impression 
from  such  a  plate  will  be  much  more  distinct  and  beautiful, 
inasmuch  as  a  mold  in  wax  will  have  its  lines  better  defined 
than  a  similar  mold  in  plaster. —  Gold  Medal. 

Mr.  Davis  had  an  exhibit  of  magnetical  apparatus 
in  the  same  class  and  year,  for  which  he  was  awarded 
a  gold  medal,  and  it  is  not  likely  that  the  award  to  Mr. 
Wilcox  would  have  passed  unchallenged  if  not  prop- 
erly made. 

Mr.  Wilcox  continued  in  business  many  years  to 
his  profit,  but  did  not  derive  as  much  financial  benefit 
from  his  inventions  as  he  might  had  he  patented  them. 
He  died  in  West  Roxbury,  Massachusetts,  February 
19,  1876. 

The  following,  from  a  letter  recently  received  from 
Mrs.  Wilcox  in  reply  to  an  inquiry  regarding  her  hus- 
band, shows  that  Mr.  Wilcox  did  not  confine  his  efforts 
entirely  to  making  printers'  plates : 

He  perfected  the  art  so  well  that  the  Massachusetts 
Charitable  Mechanic  Association,  in  1847,  awarded  him  a 
gold    medal    for    specimen    of    electrotypes.      The    American 


ELECTROTYPING.  13 

Institute  of  New  York  awarded  him  a  medal  in  1848.  He 
turned  his  attention  to  making  clock  dials  and  steam-gauge 
dials  and  all  kinds  of  ornamental  plates  for  decorating  soda 
fountains  and  other  ornamental  work.  He  invented  a  proc- 
ess of  electrotyping  the  face  of  rolls  for  dressing  cloth,  and 
received  a  medal  in  i860  from  the  Massachusetts  Charitable 
Mechanic  Association  for  the  same. 

Mr.  Daniel  Davis  —  properly  Daniel  Davis,  Jr. — 
was  a  prominent  manufacturer  of  philosophical  instru- 
ments, in  Boston.  In  1842  he  published  "  Davis'  Man- 
ual of  Magnetism,"  in  which  the  process  of  electro- 
metallurgy was  mentioned,  and  there  appeared  a  cut 
and  an  electrotype  duplicate  of  the  same.  In  the  sixth 
edition,  published  in  1847,  there  is  a  frontispiece  — 
two  pages  —  one  of  which  was  printed  from  an  origi- 
nal engraving,  on  copper,  and  the  other  from  an  elec- 
trotype duplicate  made  by  depositing  on  the  original 
for  a  matrix,  and  by  depositing  on  the  matrix  to  make 
the  plate  printed  from.  At  the  bottom  of  the  page  it 
is  stated  that  that  duplicate  was  made  by  Mr.  Davis. 
Page  53  of  that  edition  was  printed  from  an  electro- 
type made  by  Mr.  Wilcox.  The  seventh  edition  of 
Davis'  Manual,  issued  in  1848,  contains  the  following 
regarding  the  electrotype  process : 

An  engraved  copper  plate  may  be  copied  by  taking  an 
impression  on  clean  and  bright  sheet  lead  with  a  powerful 
press,  or  if  the  plate  is  small  it  may  be  pressed  by  hand  on 
the  melted  fusible  metal.  Or  a  mold  may  be  made  by  depos- 
iting copper  on  the  plate  itself,  but  care  must  be  taken  to 
prevent  adhesion  both  of  the  mold  to  the  original  and  of  the 
copy  to  the  mold.  The  duplicate  thus  obtained  will  furnish 
engravings  which  can  not  be  distinguished  from  those  printed 
from  the  original  plate,  however  elaborate  the  design  and 
delicate  the  workmanship  may  be. 


14  ELECTROTYPING. 

An  engraving  printed  from  an  electrotype  plate  by  this 
method  is  given  as  a  frontispiece  to  the  1842  manual. 

A  medal  or  engraved  plate  is  placed  in  the  solution  and 
copper  deposited  upon  it.  The  negative  wire  of  the  battery 
should  be  connected  with  the  rim  of  the  medal,  and  in  case 
of  an  engraved  plate  it  may  be  soldered  to  the  corners.  The 
deposit  is  apt  to  adhere  very  firmly,  sometimes  so  much  so 
that  its  removal  is  impossible.  This  may  be  avoided  by 
slightly  greasing  or  oiling  the  mold  and  then  brushing  it 
over  with  a  little  dry  copper  bronze. 

The  mold  thus  obtained  may  have  a  wire  soldered  to  it 
and  be  placed  in  the  solution  like  the  original  one.  In  most 
cases  it  will  be  considered  safer  to  take  a  mold  of  a  valuable 
medal  or  plate  in  soft  wax  or  by  some  of  the  other  processes 
to  be  described.  An  engraving  printed  from  an  electrotype 
plate  obtained  by  this  process  is  given  as  a  specimen  in  the 
1847  manual. 

In  the  same  edition  there  is  the  following  notice: 

This  book  is  believed  to  be  the  first  ever  electro-stereo- 
typed throughout.  A  single  page  (the  53d)  of  "  Davis'  Man- 
ual of  Magnetism,"  published  in  August,  1847,  was  previously 
electrotyped  by  the  subscriber  in  the  same  manner.  The 
advantages  of  this  process  are :  First,  its  durability,  the 
copper  face  of  the  type  and  illustrations  lasting  many  times 
longer  than  the  type-metal;  and  second,  the  blackness  of  the 
impression  taken  from  copper. 

I  am  prepared  to  execute  any  orders  for  printed  work  in 
the  above  style,  of  which  the  present  book  is  an  example,  and 
to  execute  any  number  of  facsimiles  of  engraved  copper 
plates  and  of  whatever  size.  The  face  of  each  electrotype 
copy  is  harder  and  more  durable  than  the  rolled  copper. 

I  am  also  prepared  to  execute  plates  of  electrotype  copper 
for  engraving  of  greater  purity  and  uniformity  than  can 
otherwise  be  prepared. 

I  have,  within  two  years,  electrotyped  a  large  number  of 
wood  cuts,   many   of  which  have  been  in  constant  use  and 


ELECTROTYPING,  15 

which  have  answered  every  expectation  as  to  their  durability 
and  the  perfect  character  of  the  impression.^ 

The  report  of  the  Massachusetts  Charitable  Mechanic 
Association,  taking  the  lowest  estimate,  assigns  to  these  a 
durability  six  times  greater  than  that  of  the  type-metal  stereo- 
types. The  slight  additional  expense  of  the  electro-stereo- 
types is  therefore  in  no  proportion  to  their  comparative  value. 

Ornamental  work  and  every  branch  of  the  art  of  electro- 
typing  will  receive  the  attention  of  the  subscriber. 

J.  W.  Wilcox. 

In  1853,  an  improvement  in  the  Smee  battery  was 
suggested  by  Mr.  Adams,  and  immediately  adopted  by 
electrotypers  in  America  and  Europe.  Other  improve- 
ments of  a  more  or  less  important  nature  were  made 
by  Mr.  Adams,  Mr.  Wilcox,  Mr.  Filmer  and  others, 
and  by  1858-59  the  electrotyping  business  may  be  said 
to  have  become  established  on  a  practical  basis ;  so 
much  so  that  the  process  was  quite  generally  employed 
for  the  reproduction  of  wood  cuts. 

In  the  meantime  electricians  had  been  busy  with 
the  problem  of  producing  a  continuous  current  of  elec- 
tricity by  mechanical  means  which  could  be  substi- 
tuted for  the  battery.  Machines  more  or  less  useful 
for  this  purpose  were  constructed  by  Dr.  W.  Siemens, 
of  Berlin,  in  1857.  Between  i860  and  1870,  Gramme, 
Schuckert,  Weston,  Brush,  and  Wilde,  brought  out 
improvements  of  more  or  less  value.  The  Wilde 
machines  were  the  first  to  be  used  to  any  extent  for 
electrotyping,  and  were  first  adopted,  about  1872,  by 
Frank  Leslie  and  Lovejoy,  Son  &  Co.,  of  New  York 
City.  They  accomplished  a  revolution  in  the  art  by 
reducing  the  time  required  to  deposit  a  shell  to  about 
three  hours.     Invaluable  as  these  first  machines  were 


16  ELECTROTYPING. 

to  the  electrotyping  trade,  they  soon  gave  place  to 
improved  types,  until  at  the  present  time  it  is  possible 
to  produce  an  electrotype  shell  thick  enough  for  ordi- 
nary purposes  in  one  hour  or  less. 

Improvements  in  molding,  blackleading  and  finish- 
ing machinery  have  kept  pace  with  the  advancing 
methods  of  electrotyping  proper.  In  1855,  Mr.  J.  A. 
Adams  invented  a  blackleading  machine  with  a  vibrat- 
ing brush  and  traveling  carriage.  In  1856,  Mr.  Filmer 
patented  a  method  of  backing  electrotype  shells,  by 
means  of  which  the  shell  was  held  down  by  springs 
during  the  operation  of  casting.  In  1858,  Mr.  S.  P. 
Knight  invented  an  improvement  in  the  preparation  of 
electrotype  molds  for  the  bath  which  was  of  great 
value  to  the  trade  and  is  universally  employed  at  the 
present  time.  His  invention  consisted  in  precipitating 
a  thin  film  of  copper  on  the  mold  previous  to  immers- 
ing it  in  the  bath.  This  is  accomplished  by  flooding 
the  mold  with  a  solution  of  sulphate  of  copper  and  then 
dusting  iron  filings  over  it.  The  effect  of  the  operation 
is  to  cause  the  deposition  of  copper  to  begin  immedi- 
ately over  the  entire  surface,  instead  of  beginning  only 
at  the  points  of  contact  and  spreading  slowly  there- 
from to  other  portions  of  the  mold.  Mr.  Knight  also 
invented,  in  1871,  a  process  for  applying  blacklead  to 
the  molds  in  the  form  of  a  solution,  distributing  it 
over  the  face  of  the  mold  by  means  of  a  traveling  rose 
nozzle. 

Many  other  improvements  of  a  minor  nature,  which 
we  have  not  space  to  describe,  have  been  made  from 
time  to  time,  and  the  art  of  electrotyping  may  be  said 
to  be  now  in  a  high  state  of  perfection. 


ELECTROTYPING.  17 

In  1857,  Alfred  Smee  made  the  remark  that  "  elec- 
trotyping  is  likely  to  be  useful  for  the  Bible,  Shakes- 
peare, '  Pilgrim's  Progress,'  or  works  that  have  a  large 
circulation."  But  the  world  has  made  wonderful  prog- 
ress in  forty  years,  and  the  art  of  electrotyping  has 
kept  up  with  the  procession.  Improved  methods,  labor- 
saving  machinery,  cheapening  material  and  the  skill 
which  comes  from  long  experience  have  combined  to 
reduce  the  cost  and  improve  the  quality  of  the  product, 
and  to-day  electrotyping  has  become  an  indispensable 
auxiliary  to  the  printing  business.  It  is  perhaps  safe 
to  say  that  seventy-five  per  cent  of  the  books  published 
during  the  last  decade  have  been  electrotyped,  to  say 
nothing  of  innumerable  engravings  and  jobs  of  all 
kinds  which  have  passed  through  the  electrotypers' 
hands.  Fifty  years  ago  there  were  in  existence  per- 
haps a  dozen  electrotyping  plants.  There  are  in  the 
United  States  alone  about  two  hundred  and  fifty  estab- 
lishments having  an  estimated  annual  output  of  over 
$5,oOo,ooo.  To  such  proportions  has  grown  a  business 
that  had  its  beginning  a  half  a  century  ago  in  a  quart 
jar. 


18  ELECTROTYPING. 


CHAPTER   II. 

THE    BATTERY. 

ELECTROTYPING  as  applied  to  the  manufacture 
of  printing  plates  may  be  briefly  described  as 
follows  :  A  mold  of  the  object  to  be  copied  is  taken  in 
beeswax  and  suspended,  together  with  a  plate  of  copper, 
in  an  acidulated  solution  of  copper  sulphate.  The  mold 
is  attached  to  the  negative  pole  of  a  battery  or  dynamo 
and  the  copper  plate  to  the  positive  pole.  The  electric 
current  passing  through  the  bath  decomposes  the  solu- 
tion and  sets  the  copper  free  on  the  wax  mold,  deposit- 
ing it  in  an  unbroken  sheet.  When  the  copper  shell 
has  become  of  sufficient  thickness  it  is  removed  from 
the  mold,  strengthened  with  a  backing  of  soft  metal, 
straightened,  shaved,  trimmed  and  blocked,  and  is  then 
ready  for  the  printing  press.  As  thus  described  the 
process  is  apparently  a  simple  one  ;  but  it  is,  in  fact,  an 
art  which  demands  a  high  degree  of  manipulative  skill 
and  the  closest  attention  to  detail. 

The  electric  current  which  makes  the  electrotype 
possible  must  be  of  a  certain  strength  and  tension.  If 
too  strong  or  too  weak,  the  deposited  copper  would  be 
brittle,  crystalline  or  spongy,  and  unsuitable  for  electro- 
types. It  is  obvious,  therefore,  that  the  source  of  elec- 
tricity is  a  most  important  consideration.  The  dynamo 
is  now  so  generally  employed  for  electrotyping  that  a 
detailed  description  of  the  galvanic  battery  would  seem 


ELECTROTYPING.  19 

to  be  out  of  place  were  it  not  for  the  fact  that  there  are 
possible  conditions  under  which  the  battery  may  still  be 
found  useful  —  such,  for  instance,  as  small  experimental 
work,  the  deposition  of  copper  during  the  night,  or 
under  other  circumstances  where  power  for  operating 
the  dynamo  is  not  available. 

In  discussing  the  galvanic  battery  no  effort  will  be 
made  to  consider  the  theory  either  of  its  action  or  the 
effect  of  the  current  on  the  solution.  It  will  be  suffi- 
cient to  consider  simply  those  facts  a  knowledge  of 
which  is  essential  to  the  successful  practice  of  electro- 
typing.  A  plate  of  zinc  and  a  plate  of  silver  immersed 
in  acidulated  water  and  connected  together  with  a  wire 
will  generate  a  current  of  electricity,  and  if  this  current 
is  passed  through  a  copper  sulphate  solution  under 
proper  conditions  the  solution  will  be  decomposed. 
Why  this  is  so  and  how  it  is  done  are  matters  concern- 
ing which  various  theories  have  been  published  in  books 
devoted  to  these  subjects  and  to  which  the  reader  is 
respectfully  referred. 

While  a  scientific  education  is  not  essential  to  the 
successful  practice  of  the  electrotyper's  art,  he  should 
possess  a  sufficient  knowledge  of  chemistry  and  of  the 
principles  of  electro-metallurgy  to  enable  him  to  prop- 
erly prepare  and  care  for  his  solutions  and  to  recognize 
the  cause  and  apply  the  remedy  for  the  difficulties  which 
will  occasionally  confront  him.  It  is  essential,  also,  that 
the  student  of  this  subject  shall  become  familiar  with 
certain  technical  terms  which  are  unavoidable  in  a  dis- 
cussion of  the  subject.  The  following  list  will  be  found 
to  contain  most  of  the  words  and  terms  peculiar  to 
electrotyping  : 


20  ELECTROTYPING. 

Positive  plate,  the  active  element  (zinc)  of  the  bat- 
tery. Negative  plate,  the  inactive  (silver)  element  of 
the  battery.  Positive  pole,  the  wire  attached  to  the 
silver  plate  by  which  the  current  leaves  the  battery. 
Negative  pole,  the  wire  attached  to  the  zinc  plate  by 
which  the  current  returns  to  the  battery.  Electrodes, 
the  immersed  surfaces  of  metal  or  other  conductor,  by 
which  the  current  enters  and  leaves  the  liquid.  Anode, 
the  pole  or  plate  by  which  the  current  enters  the  solu- 
tion. Cathode,  the  wax  mold  or  other  surface  receiving 
the  deposit  and  by  which  the  current  leaves  the  solu- 
tion. Volt,  the  unit  of  electro-motive  force.  Ampere, 
the  unit  of  current  strength.  Watt,  a  current  of  one 
ampere  at  the  pressure  of  one  volt. 

There  is  hardly  any  limit  to  the  number  and  variety 
of  galvanic  batteries  extant,  but  for  various  reasons  the 
one  invented  by  Mr.  Alfred  Smee  and  bearing  his  name 
has  been  found  most  suitable  for  electrotyping.  When 
a  plate  of  copper  and  a  plate  of  zinc  are  immersed  in 
acidulated  water  and  connected  together  with  a  wire,  a 
current  of  electricity  will  at  once  begin  to  circulate, 
starting  at  the  zinc,  or  positive  plate  ;  passing  through 
the  fluid  to  the  copper,  or  negative  plate,  and  thence 
through  the  connecting  wire  back  to  the  zinc.  The 
current  thus  generated  is  at  first  powerful,  but  gradu- 
ally decreases  in  strength  and  finally  ceases  altogether, 
owing  partly  to  so-called  local  action  in  the  zinc  plate 
and  partly  to  the  adherence  of  hydrogen  bubbles  to  the 
copper  plate,  which  have  the  effect  of  insulating  it. 
The  local  action  referred  to  is  caused  by  particles  of 
other  metals,  such  as  lead  and  tin,  which  are  nearly 
always   present  in   zinc   to   a   greater   or    less   extent. 


ELECTROTYPING.  21 

These  foreign  metals  form  minute  but  independent  bat- 
teries in  themselves,  which  serve  to  rapidly  dissolve  the 
zinc.  This  local  action  may  be  minimized  by  amalga- 
mating the  zinc  plate  with  mercury,  which  is  done  in 
the  following  manner :  After  thorough  cleaning  with 
caustic  potash  or  dilute  sulphuric  acid,  the  zinc  plate  is 
placed  in  a  shallow  vessel  and  every  part  of  its  surface 
carefully  coated  with  mercury  mixed  with  a  little  sul- 
phuric acid.  The  coating  may  be  applied  with  a  flan- 
nel cloth  tied  to  a  stick  or  in  any  convenient  manner, 
and  should  be  well  rubbed  in. 

The  adherence  of  hydrogen  bubbles  to  the  copper 
plate  may  be  prevented  to  a  large  extent  by  roughening 
its  surface.  Mr.  Smee  improved  upon  this  plan  by  sub- 
stituting a  silver  plate  for  the  copper  plate  and  roughen- 
ing the  surface  of  the  silver  by  platinizing.  The  first 
cost  of  silver  plates  is  considerable  and  platinizing  is 
also  an  expensive  process,  but  the  Smee  battery  is  so 
far  superior  to  the  zinc-copper  battery  for  electrotyping 
that  the  difference  in  first  cost  is  a  matter  of  small  con- 
sequence. Solid  silver  plates  are  seldom  employed  in 
the  battery,  heavily  plated  copper  plates  having  been 
found  to  answer  the  purpose  nearly  as  well.  Platinizing 
is  effected  by  suspending  the  silver  plate  in  a  saturated 
solution  of  bichloride  of  platinum  and  acidulated  water 
in  the  proportion  of  one  part  solution  to  thirty  parts 
water.  In  the  same  vessel  opposite  the  silver  plate  is  a 
porous  cell  containing  sulphuric  acid  and  water  ( i  to 
id)  with  a  zinc  plate  suspended  in  it.  On  connecting 
the  zinc  and  silver  plates  with  a  wire  the  platinum  in  the 
solution  will  be  deposited  on  the  silver  plate  in  the  form 
of  a  nearly  black  powder,  which  roughens  the  surface 


22  ELECTROTYPING. 

of  the  plate  and  effectually  prevents  the  adherence  of 
hydrogen  bubbles. 

A  battery  may  consist  of  one  or  more  sets  of  plates, 
the  number  and  size  of  plates  to  be  determined  by  the 
amount  of  work  to  be  performed.  To  produce  the  best 
results  the  surface  of  the  zinc  element  in  the  battery 
should  equal  the  cathode  surface  in  the  depositing  bath. 
That  is  to  say,  if  it  is  desired  to  deposit  copper  on  four 
molds  at  one  time,  each  one  square  foot  in  area,  then 
the  battery  should  contain  an  equal  area  of  zinc  surface; 
a  convenient  size  for  the  plates  in  a  battery  of  this 
capacity  would  be  12  by  12  inches.  A  battery  made 
up  of  four  zinc  and  two  silver  plates,  each  twelve  inches 
square,  would  deposit  a  good  quality  of  copper  over 
eight  square  feet  of  area. 

The  electro-motive  force  of  one  Smee  cell  is  sufficient 
to  deposit  copper  on  shallow  molds,  and  there  is,  there- 
fore, no  necessity  for  employing  more  than  one  cell  for 
ordinary  electrotyping,  but  care  should  be  taken  to  make 
the  cell  large  enough  to  accommodate  a  sufficient  num- 
ber of  zinc  plates  to  equal  the  area  of  the  molds  in  the 
depositing  bath.  In  this  connection  it  may  be  explained 
that  while  a  strong  current  may  be  employed  in  electro- 
typing,  but  very  little  tension  or  electro-motive  force  is 
required,  and  it  is  well  to  remember  that  the  size  of  the 
battery  or  the  number  of  plates  it  contains,  have  noth- 
ing to  do  with  its  electro-motive  force  or  the  pushing 
power  of  its  current.  A  cell  of  one  quart  capacity  has 
the  same  E.  M.  F.  as  one  of  100  gallons,  but  the 
strength  or  quantity  of  current  depends  on  the  area  of 
zinc  surface  attacked.  It  is,  therefore,  essential  in  mak- 
ing up  a  battery  for  electrotyping  to  connect  all  the  zinc 


ELECTROTYPING. 


o.q 


plates  to  one  electrode,  and  all  the  silver  plates  to  the 
other.  As  before  stated,  the  E.  M.  F.  of  one  cell  is 
sufficient  for  ordinary  electrotyping;  but  for  such  work 
as  steel  or  nickel  facing,  one  cell  would  not  have  suffi- 
cient power  to  overcome  the  resistance  offered  by  the 
iron  or  nickel  solutions,  and  it  becomes  necessary  to 
couple  two  or  more  cells  together  by  connecting  the 
zincs  of  one  cell  with  the  silvers  of  the  other.     In  this 


Fig.  I. 
Electrotype  Battery. 


way  the  power  of  the  battery  to  overcome  resistance  is 
increased  in  proportion  to  the  number  of  cells  employed, 
but  the  strength  of  the  current  remains  the  same  unless 
the  area  of  zinc  surface  attacked  should  also  be  increased. 
In  Fig.  I  is  illustrated  a  single-cell  battery  showing 
the  electrode  and  cross-rods  for  supporting  the  zinc  and 
silver  plates.  This  cell  is  i8  inches  long,  i8  inches 
deep  and  i6  inches  wide,  and  is  designed  for  four  zinc 


24  ELECTROTYPING. 

and  two  silver  plates,  each  1 2  inches  square.  This  bat- 
tery is  large  enough  to  deposit  from  eight  to  ten  feet  of 
copper  at  a  time.  The  electrodes  are  ^-inch  copper 
rods,  and  the  cross-rods  are  ^  inch  in  diameter.  The 
vat  is  constructed  of  pine  or  vvhitewood  planks,  bolted 
together,  and  is  lined  with  asphaltum. 

To  obtain  satisfactory  shells  at  a  minimum  expense, 
the  battery  should  receive  careful  attention.  The  zinc 
plates  must  be  kept  thoroughly  amalgamated  to  prevent 
waste.  With  this  object  in  view  the  plates  should  be 
frequently  examined,  and  when  dark  spots  are  observed 
the  plate  should  be  reamalgamated.  When  not  in 
action  the  zinc  plates  should  always  be  removed  from 
the  cell.  The  battery  should  be  stirred  as  often  as  every 
other  day  to  equalize  the  solution,  which  becomes  dense 
from  the  addition  of  sulphate  of  zinc.  A  little  acid  and 
water  must  also  be  added  from  time  to  time  to  keep  up 
the  strength  of  the  battery.  In  mixing  acid  and  water 
the  acid  should  always  be  added  to  the  water,  and 
this  should  be  done  very  slowly  and  carefully  to  avoid 
sudden  heat  and  consequent  danger  of  explosion.  The 
silver  plates  require  very  little  attention  except  an  occa- 
sional washing,  but  should  be  platinized  two  or  three 
times  a  year  if  in  constant  use. 

After  being  in  action  about  a  week  the  battery 
usually  becomes  so  impregnated  with  sulphate  of  zinc 
that  the  addition  of  acid  has  little  or  no  effect  upon  it. 
If  the  quantity  of  sulphate  becomes  excessive,  it  will 
crystallize  on  the  positive  element  and  entirely  stop  the 
action  of  the  battery.  When  such  conditions  appear, 
it  is  better  to  throw  away  the  contents  of  the  battery 
than  to  attempt  a  remedy. 


ELECTROTYPING.  25 


CHAPTER    III. 

THE    DYNAMO. 

AS  previously  stated,  there  are  certain  conditions 
.  under  which  the  galvanic  battery  may  be  found 
useful  as  a  current  generator  for  electrotyping,  but  it 
should  be  understood  that  in  every  respect  except  the 
quality  of  copper  deposited  the  battery  is  inferior  to  the 
dynamo.  Compared  with  the  machine  the  battery  is 
both  slow  and  expensive.  A  shell  which  would  require 
twelve  hours'  time  to  deposit  with  the  battery  may  be 
deposited  in  one  hour  with  the  dynamo,  and  leaving  the 
time  element  out  of  consideration  the  actual  cost  of 
deposition  by  the  battery  method  is  probably  six  times 
as  great  as  by  the  machine.  Theoretically  a  pound  of 
copper  should  be  obtained  for  each  pound  of  zinc  and 
acid  consumed  in  the  battery,  but  in  actual  working  the 
consumption  of  zinc  amounts  to  nearly  two  pounds. 
With  zinc  at  7  cents  per  pound,  a  copper  shell  tAd  of 
an  inch  in  thickness  would  cost  for  deposition  about 
3  cents  per  square  foot.  On  the  other  hand,  a  dynamo 
with  a  capacity  of  160  square  feet  per  day  can  be  opera- 
ted at  an  expense  for  power  of  not  to  exceed  75  cents, 
or  about  J^  cent  per  square  foot.  The  current  gener- 
ated by  the  dynamo  is  powerful,  uniform,  and  easily 
managed;  while  the  machine  itself  requires  but  little 
attention,  is  clean  and  always  ready  for  business. 

Dynamos  of  various  sizes  and  types  are  now  manu- 
factured specially  for  electrotyping  and  plating  purposes. 


26 


ELECTROTYPING. 


and  the  electrotyper  is  offered  an  unlimited  assortment 
from  which  to  choose.  Dynamo  building  is  no  longer  a 
mystery,  and  its  principles  are  so  well  understood  that 
there  is  no  more  excuse  for  building  an  inferior  machine 
than  there  would  be  for  building  a  poor  steam  engine. 


Fig.  2. 
Electrotvping  Dynamo. 


There  is,  therefore,  little  danger  of  disappointment  if 
the  dynamo  is  purchased  from  a  reputable  manufac- 
turer, provided  the  requirements  of  the  machine  are 
thoroughly  understood  by  purchaser  and  seller.  It 
would  be  folly  to  attempt  to  force  a  ten-horse  engine  to 
do  work  requiring  twenty  horse-power,  and  it  is  equally 


ELECTROTYPING.  27 

foolish  to  expect  a  dynamo  to  do  more  work  than  it  is 
designed  to  do.  Here  is  where  an  error  is  often  made. 
To  save  the  few  dollars  difference  in  first  cost  a  small 
machine  is  installed,  overloaded  and  condemned,  when 
the  fault  is  not  in  the  machine  but  in  the  man  who  over- 
loads it.  Competition  between  builders  of  dynamos 
induces  them  to  claim  for  their  respective  machines  the 
utmost  limit  of  their  capacity  when  running  under  the 
most  favorable  conditions,  and  as  the  conditions  are 
not  always  favorable,  dissatisfaction  results.  The  elec- 
trotyper  should  himself  have  a  definite  idea  of  the 
number  of  square  feet  he  will  require  to  deposit  at  one 
time  and  the  speed  at  which  he  wishes  to  work,  for  it 
is  true  in  electrotyping  as  in  mechanics  generally  that 
' '  we  cannot  get  something  for  nothing. ' '  A  dynamo 
which  will  deposit  loo  feet  of  shells  in  two  hours  will 
deposit  only  50  feet  in  one  hour,  and  if  a  rapid  rate  of 
deposition  is  desired  a  correspondingly  large  machine 
must  be  employed. 

Authorities  differ  somewhat  in  their  estimates  as  to 
the  maximum  current  density  which  may  be  employed 
in  electrotyping  ;  but  it  is  safe  to  figure  on  about  twenty- 
five  amperes  per  square  foot  with  the  solution  at  rest 
and  about  fifty  amperes  with  the  solution  in  motion. 
On  this  basis,  a  dynamo  of  500  amperes,  with  an  E.  M. 
F.  of  i)^  volts  working  one  vat,  would  deposit  about 
twenty  feet  at  a  time.  If  speed  were  no  object  a  some- 
what larger  area  could  be  covered  by  reducing  the  volt- 
age. The  most  economical  method  of  utilizing  the 
current,  and  the  one  generally  employed,  is  to  connect 
the  machine  to  two  vats  in  series.  By  this  means  the 
current   is   utilized  in  both  baths  before   it  returns  to 


28 


ELKCTROTVPING. 


05 


the  machine  and  the  capacity  of  the  dynamo  is  nearly 
doubled.  Fig.  3  is  a  plan  view  of  a  double  vat,  show- 
ing the  method  of  con- 
necting the  dynamo  in  ^  ^^ 
scries.  The  current  leav- 
ing the  machine  traverses 
the  electrode  a,  enters  the 
solution  in  the  first  vat  by 
anode  ( i ) ,  passes  through 
the  solution  and  leaves 
the  vat  by  cathode  (3) 
and  the  dead  rod  c,  enters 
the  second  vat  by  the 
anode  (2),  leaves  it  by 
cathode  (4)  and  returns 
to  the  dynamo  by  elec- 
trode d.  By  this  method 
the  current  is  made  to  do 
duty  in  both  vats  ;  but 
inasmuch  as  the  resist- 
ance of  two  solutions  is 
double  the  resistance  of 
one  solution,  the  E.  M. 
F.  of  the  current  must  be 
double  what  would  be  re- 
quired for  a  single  bath. 
If  one  volt  pressure  will 
overcome  the  resistance 
of  one  solution  to  an  ex- 
tent sufficient  to  accom- 
plish a  satisfactory  rate  of  deposition,  then  two  volts  will 
be  required  to  effect  the  same  rate  of  deposition  in  two 


Fig.  3. 

Dynamo  Connkctions  on  Double 
Vat. 


ELECTROTYPING.  29 

vats.  It  should  be  remembered  that  within  certain 
Hmits  the  rate  of  deposition  depends  on  the  strength  of 
current  employed,  and  this  fact  should  have  due  con- 
sideration in  estimating  the  capacity  of  a  machine.  A 
good  quality  of  copper  may  be  deposited  with  a  current 
density  of  thirteen  or  fourteen  amperes  per  square  foot, 
but  the  rate  of  deposition  would  be  slow.  On  the  other 
hand,  fifty  or  more  amperes  per  square  foot  may  be  em- 
ployed, under  proper  conditions,  with  a  corresponding 
increase  in  the  rate  of  deposition,  but  at  an  additional 
expense  for  power.  In  the  first  case,  roughly  speaking, 
about  four  hours  would  be  required  to  deposit  a  shell 
TT)*i)5  of  an  inch  in  thickness,  while  in  the  latter  case  one 
hour  would  be  sufiicient  to  deposit  the  same  weight  of 
copper.  In  the  first  case  a  500-ampere  machine  on  one 
vat  would  deposit  about  thirty-five  feet  at  one  time, 
while  in  the  latter  case  it  would  deposit  only  one-fourth 
as  large  an  area,  but  would  accomplish  the  work  four 
times  as  fast.  In  the  long  run  the  result  would  be  the 
same  so  far  as  the  total  quantity  of  copper  deposited  is 
concerned,  and  where  speed  is  no  object  the  former 
current  density  is  preferable  because  more  economical 
in  power. 

It  has  been  stated  that  fifty  or  more  amperes  per 
square  foot  of  cathode  surface  may  be  utilized  in  elec- 
trotyping  under  proper  conditions,  and  that  shells  of 
average  weight  may  be  thus  deposited  in  about  one 
hour.  To  effect  such  a  rapid  rate  of  deposition  it  is 
essential,  first,  that  the  dynamo  shall  be  constructed  to 
supply  a  large  volume  of  current  without  dangerously 
heating  the  machine;  second,  the  solution  should  be 
properly  proportioned;  third,  the  solution  or  the  anodes 


30  ELECTROTYPING. 

must  be  kept  in  constant  motion;  and  fourth,  all  con- 
nections must  be  of  large  size,  and  the  points  of  contact 
clean  and  firmly  made. 

Large  plants,  in  which  more  than  two  vats  are  oper- 
ated, usually  employ  more  than  one  machine.  In  other 
words,  it  is  considered  good  policy  to  employ  two  dyna- 
mos for  four  vats,  rather  than  to  couple  all  four  vats  to 
one  dynamo.  The  object  of  such  an  arrangement  is 
that  one-half  the  plant  may  be  discontinued  during  a 
dull  season,  and  it  also  permits  the  use  of  low  voltage 
machines,  such  as  are  carried  in  stock  by  the  manufac- 
turers. From  what  has  been  previously  said  on  this 
subject,  it  will  be  obvious  that  a  dynamo  working  four 
vats  in  series  would  require  to  have  four  times  the  volt- 
age needed  for  one  vat,  and  twice  the  voltage  needed 
for  two  vats.  If  a  very  rapid  rate  of  deposition  is 
desired,  a  machine  working  four  vats  would  need  to  be 
operated  at  a  tension  of  eight  or  ten  volts,  whereas  a 
tension  of  four  to  five  volts  would  be  sufficient  for  two 
vats.  Machines  of  the  latter  capacity  are  of  standard 
make,  while  it  is  probable  that  a  ten-volt  dynamo  would 
have  to  be  specially  constructed. 

When  purchasing  a  dynamo,  consideration  should 
be  given  to  the  possible  maximum  output  of  the  foun- 
dry, as  well  as  the  rate  of  deposition  desired.  If  the 
plant  includes  but  one  molding  press  and  one  black- 
leading  machine,  and  rapid  work  is  not  imperative,  a 
dynamo  of  450  amperes  and  two  volts  would  take  care 
of  all  the  work  which  could  be  turned  out,  for  such  a 
machine  working  two  vats  in  series  would  deposit  from 
forty  to  fifty  square  feet  at  one  time,  and  would  deposit 
a  sufficiently  heavy  shell  in  about  three  hours.      In  other 


ELECTROTYPING.  31 

words,  it  would  deposit  about  fifteen  feet  per  hour, 
which  would  probably  be  the  limit  of  the  capacity  of  a 
foundry  of  the  indicated  size.  If,  however,  it  is  desired 
to  deposit  fifteen  feet  every  hour  instead  of  forty-five 
feet  every  three  hours,  a  much  larger  machine  would  be 
required,  for,  as  has  been  before  stated,  the  rate  of 
deposition  depends  principally  on  the  strength  of  cur- 
rent employed;  and  while  a  sufficient  current  density 
for  a  limited  number  of  shells  could  be  obtained  from 
the  small  machine,  it  could  be  applied  to  only  one  vat 
at  a  time,  because  sufficient  E.  M.  F.  could  not  be 
generated  to  force  the  current  through  two  solutions  at 
the  maximum  speed.  The  capacity  of  the  machine  in 
square  feet  of  cathodes  which  could  be  deposited  at  one 
time  would,  therefore,  be  cut  down  to  one-quarter  of 
the  surface  which  could  be  covered  at  slow  speed. 

To  further  illustrate  this  point,  we  will  suppose  a 
dynamo  of  450  amperes  and  2  ^  volts  to  be  connected 
with  two  baths  in  series.  Each  bath  would  then  be 
supplied  with  a  current  of  i  ^  volts  pressure,  and  the 
quantity  of  current  utilized  would  be  approximately  30 
amperes  per  square  foot  of  cathode.  The  total  capacity 
of  the  machine,  450  amperes,  divided  by  30,  gives  15, 
the  number  of  feet  which  can  be  deposited  at  one  time 
in  each  bath,  or  a  total  of  30  feet.  Now,  if  it  is  desired 
to  double  the  rate  of  deposition,  it  becomes  neces- 
sary to  double  the  pressure  of  the  current,  which  would 
mean  5  volts  instead  of  2^.  As  the  small  machine 
cannot  be  made  to  produce  5  volts,  the  only  alternative 
is  to  disconnect  one  of  the  vats.  We  now  have  2^ 
volts  applied  to  one  bath,  and  are  using  about  60 
amperes  per  square  foot  of  cathode  ;  450  divided  by  60 


32"  ELECTROTYPING. 

gives  7j^  as  the  maximum  number  of  feet  which  could 
be  deposited  at  one  time,  and  this  is  in  theory  only,  for 
in  actual  practice  it  is  found  impracticable  to  deposit 
more  than  5  feet,  owing  to  the  tendency  of  the  machine 
to  heat.  The  economy  in  operating  a  large  dynamo  for 
rapid  deposition  is  thus  plainly  evident. 

The  results  of  a  series  of  tests  recently  conducted 
by  the  writer  are  given  below  : 

Dynamo No.  i  Lloyd 

Speed 1.350 

Volts  2% 

Amperes  per  square  foot,  about 51 

Number  of  baths i 

Area  of  cathodes,  square  feet 7 

Time  of  exposure,  minutes 60 

Thickness  of  deposit,  inches 003 

A  similar  test  of  a  No.  i  Eddy  dynamo  produced  the 
same  result.  It  should  be  said  that  during  the  tests 
these  machines  were  both  operated  at  higher  speeds 
than  those  mentioned,  with  the  result  that  shells  .007 
of  an  inch  were  deposited  in  one  hour;  but  owing  to 
heat  generation  only  two  or  three  square  feet  of  cathode 
surface  could  be  exposed  at  one  time. 

A  test  of  a  larger  machine  resulted  as  follows  : 

Dynamo No.  2  Lloyd 

Speed 1,000 

Volts,  per  vat 2^ 

Amperes  per  square  foot  of  cathode,  about.         54 

Number  of  baths  in  series 2 

Area  of  cathodes,  square  feet 20 

Time  of  exposure,  minutes 60 

Thickness  of  shell,  inches 0035 

These  tests  indicate  that  a  dynamo  of  800  amperes 
and  5  volts,  working  two  baths  in  series,  will  deposit, 


ELECTROTYPING.  33 

without  undue  heating,  about  twenty-eight  feet  of  shells 
per  hour  ;  while  a  450-ampere,  2^ -volt  dynamo  will 
only  deposit  about  seven  feet  per  hour.  It  appears, 
therefore,  that  rapid  deposition  is  not  practicable  with  a 
small  machine.  However,  the  difference  in  cost  of 
installation  is  of  slight  moment  in  view  of  the  increased 
product  of  the  large  machine,  and  should  not  stand  in 
the  way  of  the  better  service,  particularly  as  the  larger 
dynamo  will  perform  a  limited  volume  of  work  equally 
as  well  as  the  smaller,  and  at  only  a  nominal  increase  in 
expense  for  power.  In  later  tests  with  larger  dynamos 
and  an  agitated  solution  the  current  strength  was 
increased  to  125  amperes  per  square  foot,  with  the 
result  that  practical  shells  were  produced  in  fifteen 
minutes.  The  above  mentioned  tests  are  given  with 
the  object  of  indicating  how  present  facilities  may 
be  utilized  to  the  best  advantage  by  electrotypers 
whose  machines  equal  or  excel  the  capacity  of  the 
No.   2   Lloyd. 

Dynamos,  as  a  rule,  require  but  little  attention,  but 
should  always  be  kept  clean  and  well  oiled.  The  com- 
mutator, in  particular,  should  be  occasionally  cleaned 
with  a  piece  of  fine  sandpaper  (not  emery  paper)  and 
then  wiped  off  with  a  clean,  damp  cloth.  Slow-speed 
machines  require  no  lubricant  on  the  commutator  other 
than  an  occasional  wiping  with  a  damp  cloth.  On  high- 
speed machines  a  very  little  vaseline  may  be  applied 
every  two  or  three  hours.  The  brushes  should  fit  the 
commutator  fairly  well,  otherwise  there  will  be  a  ten- 
dency to  spark  and  heat.  Sparking  should  never  be 
permitted,  as  it  rapidly  wears  the  commutator.  It  may 
often  be  prevented  by  moving  the  brushes  a  little  one 
3 


34  ELECTROTYPING. 

way  or  the  other  from  the  position  in  which  the  spark- 
ing occurs. 

For  nickel-facing  electrotypes  a  current  tension  of 
2^  to  3  volts  is  required,  and  for  this  work  a  separate 
dynamo  is  usually  employed ;  but  when  the  electrotyp- 
ing  dynamo  is  sufficiently  powerful  the  nickel  bath  may 
be  operated  in  connection  with  the  copper  baths  by  pro- 
viding it  with  a  resistance  coil  for  regulating  the  strength 
of  current  supplied  to  it.  With  a  dynamo  operating  at 
2^  volts  it  would  be  possible  to  work  the  nickel  bath 
without  a  resistance  coil,  as  in  this  case  a  sufficient  vari- 
ation of  current  strength  could  be  obtained  by  varying 
the  distance  between  the  cathodes  and  anodes.  But  if 
the  tension  exceeds  23^  volts,  a  means  must  be  pro- 
vided for  cutting  down  the  current  to  the  point  best 
suited  to  the  conditions  of  the  work. 


ELECTROTYPING.  35 


CHAPTER   IV. 

THE    BATH. 

THE  depositing  bath  for  electro  typing  in  copper  con- 
sists of  a  solution  of  blue  vitriol  acidulated  with 
sulphuric  acid.  Copper  sulphate,  blue  vitriol,  or  blue 
stone,  as  it  is  variously  termed,  forms  crystals  which 
when  unadulterated  are  pure  blue  in  color  and  cannot  be 
mistaken  for  any  other  chemical.  A  green  tinge  indi- 
cates the  presence  of  sulphate  of  iron  and  should  be 
rejected.  While  the  color  is  a  sufficient  guide  to  the 
purity  of  the  sulphate  it  may  be  further  tested  by  boil- 
ing a  small  quantity  of  the  solution  with  a  little  nitric 
acid  and  adding  spirits  of  ammonia  in  excess.  The 
presence  of  iron  will  be  indicated  by  brown  flakes. 
Distilled  water  or  filtered  rain  water  should,  if  possible, 
be  used  in  making  the  solution.  If  rain  or  distilled 
water  cannot  be  conveniently  obtained,  well  or  lake 
water  will  answer,  but  should  always  be  thoroughly 
boiled  and  filtered. 

Sulphuric  acid  (oil  of  vitriol)  for  acidulating  the 
solution  should  be  used  pure  and  concentrated.  The 
crude  acid  contains  arsenic  which  renders  it  unfit  for  use 
in  electrotyping  solutions.  The  pure  acid  has  a  specific 
gravity  of  1.84.  It  may  be  recognized  by  mixing  one 
part  with  twenty-five  parts  of  distilled  water  and  com- 
pounding with  a  few  drops  of  barium  chloride,  when  a 
white  precipitate  will  be  formed.     In  diluting  acid  with 


36  ELECTROTYPING. 

water  it  should  always  be  added  to  the  water  very  slowly 
and  with  constant  stirring,  as  the  heat  generated  by  the 
contact  of  the  acid  and  water  might  otherwise  be  suffi- 
cient to  cause  a  dangerous  explosion.  Sulphuric  acid 
is  exceedingly  corrosive  and  should  always  be  kept  in 
glass  bottles  or  carboys. 

The  copper  solution  is  the  least  troublesome  of  all 
electrolytes.  While  some  baths  require  accurate  pro- 
portionment,  the  use  of  distilled  water,  and  even  an 
exact  degree  of  temperature  for  their  successful  opera- 
tion, the  copper  bath  may  be  widely  varied  in  propor- 
tion and  will  work  well  under  considerable  variation  ot 
temperature.  Nevertheless,  there  are  certain  limits  oi 
proportionment  which  must  be  observed  to  obtain  rapid 
deposition  of  a  good  quality  of  copper;  for,  while  the 
rate  of  deposition  depends  very  largely  on  the  strength 
of  current,  it  is  essential  that  the  solution  be  constituted 
to  work  in  harmony  with  the  current.  The  essential 
qualities  of  the  solution  are  to  present  the  least  possible 
resistance  to  the  electric  current  and  to  dissolve  the 
anode  with  the  same  rapidity  with  which  the  copper 
from  the  solution  is  deposited  on  the  cathode.  A  solu- 
tion of  copper  sulphate  without  the  addition  of  acid 
will  conduct  electricity,  but  its  resistance  is  such  that 
a  very  strong  current  is  required  to  overcome  it.  Von 
Hiibl  found  that  the  minimum  current  density  per 
square  foot  of  cathode  in  a  fifteen-per-cent  blue  vitriol 
solution  without  acidulation  is  24.  i  amperes,  while  the 
same  solution  with  six  per  cent  sulphuric  acid  added 
required  but  13.9  amperes.  But  while  it  is  thus  shown 
that  the  addition  of  sulphuric  acid  lessens  the  resistance 


ELECTROTYPING,  37 

of  the  solution,  there  remains  a  wide  difference  of  opin- 
ion as  to  the  maximum  quantity  of  acid  which  may  be 
employed  to  advantage. 

It  is  not  difficult  to  prepare  a  solution  which  with  a 
moderate  current  will  deposit  copper  of  good  quality  at 
a  moderate  speed.  As  an  evidence  of  this  fact  it  may 
be  stated  that  it  would  be  difficult  to  find  two  solutions 
exactly  similar,  the  variations  extending  from  twelve  to 
twenty-two  per  cent  blue  vitriol,  and  from  two  to  eight 
per  cent  acid.  However,  there  is  no  question  but  that 
a  moderately  rich  solution  is  preferable  and  even  neces- 
sary for  rapid  work.  A  solution  poor  in  copper  will 
deposit  quickly,  but  the  shells  are  apt  to  be  porous  and 
granular.  On  the  other  hand,  a  solution  too  rich  in 
copper  will  deposit  slowly  and  in  crystalline  form. 
Deposits  of  this  nature  are  specially  noticeable  when  a 
weak  current  is  employed,  and  it  is  also  noteworthy 
that  a  poor  solution  is  much  more  apt  to  produce  gran- 
ular deposits  when  the  current  is  strong.  From  these 
facts  it  appears  that  a  richer  solution  may  be  employed 
with  a  strong  than  with  a  weak  current.  Almost  any 
kind  of  a  solution,  within  reasonable  limits,  will  do  good 
work  if  the  current  strength  is  adapted  to  work  in  har- 
mony with  it.  That  is  to  say,  by  observing  the  quality 
of  copper  deposited  and  increasing  or  decreasing  the 
current  strength  as  the  conditions  demand.  For  in- 
stance, if  a  pulverulent  deposit  is  obtained  it  is  an  indi- 
cation that  the  current  is  too  strong  or  the  solution  too 
weak,  and  the  defect  may  be  most  easily  remedied  by 
reducing  the  current  strength  either  by  means  of  a 
switchboard  or  by  decreasing  the  speed  of  the  dynamo. 


38  ELECTROTYPING. 

On  the  other  hand,  a  crystalline,  brittle  deposit  indi- 
cates a  weak  current  or  a  rich  solution,  and  may  be 
remedied  by  increasing  the  dynamo  speed.  However, 
if  rapid  deposition  is  desired  the  solution  must  be  con- 
stituted to  work  with  a  strong  current,  and  defects  in 
the  deposit  should  be  remedied,  so  far  as  possible,  by 
changing  the  solution  rather  than  the  dynamo,  inas- 
much as  a  reduction  in  the  speed  of  the  machine  would 
retard  the  rate  of  deposition.  Of  course,  there  are 
well-defined  limits  to  the  current  strength  which  may 
be  effectively  employed  with  any  solution,  and  it  should 
be  the  object  of  the  operator  to  determine  the  highest 
effective  point  of  harmony  between  the  two.  With 
the  bath  at  rest,  a  fourteen  to  sixteen  per  cent  solution 
acidulated  with  two  to  three  per  cent  sulphuric  acid  and 
a  current  density  of  fifteen  to  eighteen  amperes  per 
square  foot  has  been  found  most  satisfactory.  An  agi- 
tated solution  may  be  made  somewhat  richer  if  a 
stronger  current  be  employed,  say  eighteen  to  twenty 
per  cent  blue  vitriol  and  three  to  six  per  cent  acid. 
The  depositing  vat  for  the  copper  solution  should  be 
solidly  constructed  of  pine  or  whitewood  planks  bolted 
together  and  lined  with  sheet  lead  united  at  the  corners 
by  ' '  burning ' '  or  melting  the  sheets  together.  Solder- 
ing will  not  answer,  as  the  acid  in  the  solution  will 
attack  the  solder,  and  soon  eat  its  way  through.  The 
vat  should  preferably  be  partitioned  into  two  compart- 
ments, in  order  that  the  dynamo  may  be  operated  in 
series,  as  previously  described.  It  is  essential  also  that 
the  vat  shall  be  of  ample  size.  The  resistance  presented 
to  the   electric  current   by  the   solution   is   enormous, 


ELECTROTYPING. 


39 


and  only  a  great  area  will  compensate  for  its  lack  of 
conductivity.  At  least  loo  gallons  of  solution  should 
be  provided  for  each  twenty  feet  of  cathode  surface 
exposed.  A  convenient  size  and  shape  of  depositing 
vat  is  shown  in  Fig.  4.     The  length  is  60  inches,  width 


Fig.  4. —  Electrotyper's  Depositing  Vat. 

30  inches,  and  depth  26  inches.  It  will  contain  about 
200  gallons  of  solution,  and  will  accommodate  about 
ten  cases  of  average  size  in  each  compartment. 

In  mixing  the  solution  the  vat  should  be  about  two- 
thirds  filled  with  rain,  distilled  or  boiled  water.  The 
blue  vitriol  may  be  conveniently  dissolved  by  suspending 
it  in  cheese-cloth  bags  just  under  the  surface  of  the 
water.  As  the  water  becomes  saturated  it  will  sink  to 
the  bottom  of  the  vat,  and  should  be  frequently  stirred 
and   tested  with   a    Baume    hydrometer,     when    14  or 


40  ELECTROTYPING. 

15  degrees  is  indicated  on  the  instrument  the  bags 
of  vitriol  may  be  removed  and  sulphuric  acid  added 
to  the  solution,  with  constant  stirring,  until  the  reading 
of  the  hydrometer  is  increased  two  or  three  degrees. 
This  solution  will  work  well  with  a  moderate  current. 
If  the  current  strength  is  more  than  20  amperes  per 
square  foot,  the  solution  may  be  enriched  by  the  addi- 
tion of  blue  vitriol  to  the  extent  of  two  or  three  degrees, 
and  if  required  as  many  degrees  of  acid  may  also  be 
added. 

The  solution  should  be  well  stirred,  and  may  be  used 
at  once,  although  it  usually  works  better  after  standing 
a  few  days. 


ELECTROTYPING.  41 


CHAPTER  V. 

STEEL,    BRASS    AND    NICKEL    BATHS. 

COPPER  is  almost  universally  employed  for  the  pro- 
duction of  electrotypes  for  printing  purposes,  and 
generally  speaking  it  is  the  most  suitable  of  all  metals 
for  this  purpose.  It  is  easily  deposited,  is  tough,  duc- 
tile, practically  non-corrosive  and  inexpensive.  How- 
ever, it  is  too  soft  to  stand  the  wear  of  very  large  edi- 
tions, and  it  does  not  print  well  with  colors  containing 
mercury,  which  chemically  attacks  copper.  To  over- 
come these  defects  it  is  customary,  when  the  circum- 
stances are  such  as  to  warrant  the  extra  labor  and 
expense,  to  face  the  copper  electrotype  with  steel,  brass 
or  nickel.  This  is  effected  (a)  by  suspending  the  fin- 
ished electrotype  in  the  proper  solution  and  depositing 
thereon  a  film  of  harder  metal,  or  {b)  by  suspending 
the  wax  or  other  mold  in  the  hard-metal  solution, 
obtaining  thereon  a  preliminary  deposit,  and  then  trans- 
ferring it  to  the  copper  bath  where  it  is  strengthened  by 
a  sufficiently  heavy  deposit  of  copper.  Of  these  meth- 
ods, the  former  is  the  more  readily  performed  and  the 
latter  the  more  accurate  in  results.  By  the  former 
method  it  is  obvious  that  only  a  very  thin  facing  can 
be  given  to  the  electrotype  without  impairing  its  accu- 
racy, and  it  is  doubtful  if  any  kind  of  a  facing  could 
be   given    to   a   fine-screen    half-tone    by   this   method 


42  ELECTROTYPING. 

without  destroying  something  of  its  delicacy.  How- 
ever, electrotype  plates  of  ordinary  character  may  have 
a  thin  facing  of  harder  metal  deposited  upon  them 
without  perceptibly  affecting  their  accuracy. 

Of  the  three  metals  employed  for  facing  electrotypes, 
nickel  is  the  more  readily  deposited  and  its  solution  the 
least  troublesome  to  manage.  It  is  malleable  and  duc- 
tile, and  nearly  or  quite  as  hard  as  iron.  Moreover, 
it  is  non-corrosive  and  altogether  is  an  ideal  metal  for 
the  purpose.  Various  solutions  are  recommended  for 
the  nickel-depositing  bath,  each  of  which  has  its  ad- 
vocates, but  many  of  them  are  more  or  less  compli- 
cated and  require  special  care  in  management.  A 
simple  bath  which  has  been  thoroughly  tested  in  some 
of  the  largest  electrotyping  establishments  in  the  coun- 
try is  made  by  dissolving  the  double  sulphate  of  nickel 
and  ammonia  in  warm  water  in  the  proportion  of  ^ 
of  a  pound  of  the  salts  in  each  gallon  of  water.  The 
procedure  is  the  same  that  has  been  recommended 
for  the  copper  solution,  i.  e. ,  the  salts  should  be  sus- 
pended in  cheese-cloth  bags  just  under  the  surface  ot 
the  water  until  entirely  dissolved,  when  the  solution 
should  be  well  stirred  and  is  then  ready  for  use.  Some 
operators  add  about  ten  per  cent  of  common  salt  to 
the  solution  for  the  purpose  of  increasing  its  conduc- 
tivity. 

The  deposition  of  iron  is  attended  with  more  or  less 
difficulty,  and  is  not  always  successfully  accomplished 
even  by  experienced  operators.  A  good  bath  for  iron 
(steel)  facing  may  be  made  by  dissolving  two  pounds 
of  the  double  sulphate  of  iron  and  ammonia  in  each 


ELECTROTYPING.  43 

gallon  of  water.  Another  bath,  recommended  by  Urqu- 
hart,  is  prepared  by  adding  a  solution  of  carbonate  of 
ammonia  to  a  solution  of  sulphate  of  iron  until  the  iron 
is  precipitated,  when  the  liquid  portion  should  be  poured 
off  and  the  precipitate  washed,  after  which  it  is  dissolved 
to  saturation  in  a  bulk  of  sulphuric  acid  equal  to  the 
volume  of  solution  required. 

Another  iron  solution  consists  of  56  pounds  of  car- 
bonate of  ammonia  dissolved  in  35  gallons  of  water  and 
supplied  with  iron  by  means  of  a  large  anode  and  an 
electric  current  from  the  dynamo. 

The  solution  which  seems  to  be  most  popular  for  the 
production  of  iron  electrotypes,  and  which  is  highly 
recommended  by  M.  Klein,  is  composed  of  equal  parts 
of  sulphate  of  iron  (green  vitriol)  and  sulphate  of  mag- 
nesia, kept  neutral  by  bags  of  carbonate  of  magnesia 
suspended  in  the  bath.  A  sufficient  quantity  of  the 
sulphates  should  be  dissolved  in  water  to  make  the  spe- 
cific gravity  1.55,  i.  e. ,  about  51°  Baum6.  This  bath 
requires  a  current  density  of  18.5  amperes  per  square 
foot.  A  peculiarity  of  all  iron  solutions  is  that  the 
anodes  must  always  be  of  large  size,  preferably  about 
eight  times  as  large  as  the  cathodes. 

The  deposition  of  brass  is  also  attended  with  some 
difficulty,  chiefly  because  it  is  composed  of  two  metals, 
one  of  which  is  positive  and  the  other  negative,  hence 
the  current  strength  requires  more  or  less  regulation  to 
insure  uniform  deposition  of  both  metals.  As  brass  is 
composed  of  copper  and  zinc,  the  salts  of  these  two 
metals  must  necessarily  form  the  basis  of  the  depositing 
solution.       A  good    brassing    solution    consists    of    16 


44  ELECTROTYPING. 

ounces  of  cyanide  of  potassium,  5  ounces  carbonate 
of  copper,  i^  ounces  carbonate  of  zinc,  i  ounce  of 
ammonia,  and  i  gallon  of  water.  The  following  formu- 
las are  recommended  by  Roseleur  and  Dr.  Langbein: 
Copper  sulphate  and  zinc  sulphate,  each  53^  ounces, 
and  crystallized  carbonate  of  soda,  15^  ounces.  Crys- 
tallized carbonate  of  soda  and  crystallized  bisulphide 
of  soda,  each  7  ounces  ;  98  per  cent  potassium  cyanide, 
8^  ounces ;  arsenious  acid,  30^  grains ;  water,  10 
quarts.  The  bath  is  prepared  by  dissolving  the  copper 
and  zinc  sulphates  in  5  quarts  of  warm  water,  and  in 
the  other  5  quarts,  the  15^  ounces  of  carbonate  of 
soda;  then  mix  both  solutions,  which  will  form  a  pre- 
cipitate of  the  carbonates  of  copper  and  zinc.  After 
setting  ten  or  twelve  hours  the  supernatant  liquor  is 
poured  off  and  sufficient  water  added  to  the  precipitate 
to  make  six  quarts  of  solution.  Now  add  to  the  bath 
with  constant  stirring  the  carbonate  and  bisulphide  of 
soda.  Dissolve  the  potassium  in  4  quarts  of  cold  water 
and  add  this  solution  to  the  first  solution  with  the  ex- 
ception of  one-half  pint,  in  which  the  arsenious  acid  is 
dissolved  by  the  aid  of  heat,  when  it  is  also  added  to 
the  bath.  This  solution  should  be  thoroughly  boiled  for 
one  or  two  hours  and  the  water  lost  by  evaporation 
replaced. 

Another  brass  solution,  which  is  less  troublesome  to 
prepare,  contains  crystallized  carbonate  of  soda,  ioj4 
ounces ;  crystallized  bisulphate  of  soda,  7  ounces  ; 
neutral  acetate  of  copper,  4.4  ounces ;  crystallized 
chloride  of  zinc,  4.4  ounces  ;  98  per  cent  potassium 
cyanide,    14. 11    ounces;    arsenious   acid,   30^  grains; 


ELECTROTYPING.  45 

water,  lo  quarts.  Dissolve  the  carbonate  and  bisul- 
phate  of  soda  in  4  quarts  of  water,  then  mix  the  acetate 
of  copper  and  chloride  of  zinc  with  2  quarts  of  water 
and  add  this  solution  to  the  first ;  retaining,  however, 
a  small  portion  of  it  in  which  to  dissolve  the  arsenious 
acid  with  the  aid  of  heat.  Finally,  add  the  arsenious 
acid  solution,  when  the  bath  becomes  clear.  Boiling 
the  bath  or  working  it  through  with  the  current  is 
required. 

The  following  solution  is  recommended  by  Watt : 
Cyanide  of  potassium,  i  pound  ;  carbonate  of  ammonia, 
I  pound  ;  cyanide  of  copper,  2  ounces  ;  cyanide  of  zinc, 
I  ounce  ;  water,  i  gallon. 

Another  brassing  solution  which  the  writer  has 
found  very  satisfactory  consists  of  16  ounces  cyanide 
of  potassium,  5  ounces  carbonate  of  copper,  i  ^  ounces 
carbonate  of  zinc,  i  ounce  ammonia,  and  one  gallon  of 
water. 

Solutions  containing  cyanides  would  immediately 
destroy  wax  or  gutta-percha  molds,  and  their  use  is 
therefore  restricted  to  plating  or  facing  electrotypes  or 
other  metallic  articles. 


46  ELECTROTYPING. 


CHAPTER  VI. 


MANAGEMENT   OF    BATHS. 


THE  acid  copper  solution  is  not  difficult  to  manage 
and  may  be  kept  for  years  in  constant  use  by 
adding  from  time  to  time  a  little  of  one  or  the  other  of 
its  constituents  as  may  be  needful  to  make  good  the 
loss  occasioned  by  various  causes.  This  loss  is  prin- 
cipally by  evaporation,  and  by  simply  adding  a  few  pints 
of  distilled  water  the  solution  may  generally  be  restored 
to  nearly  its  original  proportions. 

Under  ordinary  conditions  the  copper  withdrawn 
from  the  bath  and  deposited  on  the  cathode  is  not 
fully  replaced  by  the  anodes,  and  it  is  necessary,  there- 
fore, to  enrich  the  solution  occasionally  with  a  little 
sulphate  of  copper,  which  may  be  done  by  suspending 
just  under  the  surface  of  the  solution  a  few  pounds  of 
the  crystals  in  a  cheese-cloth  bag.  A  reduction  in  the 
content  of  copper  in  the  bath  from  this  cause  always 
produces  a  corresponding  increase  of  free  acid.  Should 
the  content  of  acid  become  excessive,  it  may  be  neu- 
tralized by  the  addition  to  the  solution  of  a  little  car- 
bonate of  copper. 

When  the  anodes  are  larger  than  the  cathodes  —  or 
when,  as  may  happen,  a  number  of  anodes  are  left  in 
the  bath,  connected  with  the  current,  while  molds  are 


ELECTROTYPING.  47 

being  prepared  for  the  depositing  process  —  the  quan- 
tity of  copper  dissolved  will  exceed  the  quantity  depos- 
ited, resulting  in  undue  concentration  of  the  solution. 
This  condition  will  be  indicated  by  a  tardy  formation 
of  the  deposit  and  the  production  of  a  shell  of  brittle 
and  crystalline  character.  Moreover,  a  dense  solution, 
unless  continuously  agitated,  is  apt  to  produce  streaky 
deposits.  An  excess  of  copper  is  further  indicated  by 
the  formation  of  crystals  of  sulphate  of  copper  on  the 
sides  of  the  vat  and  sometimes  on  the  anodes.  When 
such  conditions  appear,  the  obvious  remedy  is  to  dilute 
the  solution  with  water.  However,  the  addition  of  water 
to  make  good  the  loss  caused  by  evaporation  is  usually 
sufficient  to  remedy  any  excess  of  copper  without  further 
dilution. 

A  quiescent  solution  always  becomes  more  concen- 
trated at  the  bottom  than  at  the  top  of  the  vat.  As  a 
result  of  this  condition  the  lower  portion  of  the  anode 
will  be  dissolved  less  freely  than  the  upper  on  account 
of  the  increased  resistance;  but,  on  the  other  hand,  the 
copper  will  be  deposited  more  rapidly  on  the  lower  por- 
tion of  the  cathode  where  the  largest  quantity  of  metal 
is  in  solution.  For  the  same  reason  that  portion  of  the 
cathode  which  is  suspended  in  the  heavier  strata  of  the 
bath  is  apt  to  become  covered  with  nodules  or  excres- 
cences which  are  more  or  less  annoying  and  wasteful. 
This  difficulty  may  be  minimized  by  stirring  the  solution 
occasionally  with  a  wooden  paddle,  which  will  tem- 
porarily equalize  its  density.  The  bath  should  not  be 
stirred  while  in  use,  particularly  if  old  and  dirty,  as  the 


48  ELECTROTYPING. 

impurities  which  will  have  settled  on  the  bottom  of  the 
vat  would  be  likely  to  lodge  on  the  work  and  cause 
holes  in  the  shells.  Some  electrotypers  are  content  to 
stir  the  solutions  once  a  week,  usually  on  Saturday 
evening,  thus  giving  the  bath  thirty-six  hours  in  which 
to  settle;  but,  unless  very  dirty,  it  is  advisable  to  stir 
it  as  often  as  every  twenty-four  hours.  When  a  bath 
has  become  so  dirty  that  it  cannot  be  agitated  without 
danger  of  injuring  the  work  it  should  be  filtered. 

The  temperature  of  the  bath  should  be  kept  between 
65  and  75  degrees  Fahr.  At  65  degrees  the  best  qual- 
ity of  copper  is  produced;  but  the  quality  is  not  seri- 
ously impaired  by  raising  the  temperature  ten  degrees, 
while  the  rate  of  deposition  is  materially  increased. 
Baths  located  in  a  room  not  heated  at  night  may  be 
provided  with  a  coil  of  lead  pipe  through  which  steam 
may  be  circulated  and  the  temperature  increased  thereby 
as  desired.  Deposition  always  proceeds  sluggishly  on 
cold  mornings,  unless  some  provision  for  warming  the 
solution  is  made.  It  is  always  desirable  to  keep  the 
baths  in  a  room  separate  from  the  molding  and  finishing 
departments  in  order  to  protect  them  as  far  as  possible 
from  dust  and  flying  particles  of  metal.  It  is  also  a 
good  plan  to  keep  the  vats  covered  when  not  in  use. 

The  anodes  should  be  removed  from  the  solution 
daily,  and  thoroughly  cleaned  from  the  slime  which 
accumulates  on  them  and  which  has  the  eflfect  of  par- 
tially insulating  them. 

What  has  been  said  regarding  the  general  care  of 
the  copper  bath  applies  also  to  the  nickel  bath.     An 


ELECTROTYPING.  49 

occasional  addition  of  water  to  restore  the  loss  occa- 
sioned by  evaporation  is  imperative,  as  is  also  the  addi- 
tion of  a  few  crystals  of  nickel  salts  from  time  to  time  if 
the  bath  becomes  impoverished. 

Brass  and  iron  baths  are  more  troublesome  than 
either  copper  or  nickel.  The  brass  bath  requires  fre- 
quent building  up,  particularly  if  not  in  regular  use. 
As  brass  contains  a  larger  proportion  of  copper  than 
zinc,  the  copper  in  the  bath  becomes  first  exhausted, 
and  sufficient  carbonate  or  cyanide  of  copper,  according 
to  the  constitution  of  the  bath,  must  be  added  to  restore 
the  proper  proportions.  Cyanide  of  potassium  must 
also  be  supplied  when  the  action  of  the  bath  becomes 
sluggish  and  no  bubbles  are  observed  on  the  cathodes. 
When,  however,  there  is  a  vigorous  evolution  of  gas  it 
is  an  indication  of  an  excess  of  cyanide,  and  a  slow 
deposit  under  these  circumstances  would  be  remedied 
by  the  addition  of  the  metallic  salts.  A  deposit  of  light 
color  would  indicate  a  want  of  copper  in  the  solution, 
and  a  dark  color  a  lack  of  zinc.  However,  the  color  is 
not  a  reliable  guide,  as  it  may  be  caused  by  a  variation 
in  the  density  of  current  employed.  A  weak  current 
would  deposit  more  copper  than  zinc  and  would  give  its 
color  to  the  deposit,  while  a  strong  current  deposits 
both  metals  in  their  proper  proportions.  Constant 
watchfulness  is  required  to  keep  the  brass  bath  in  good 
working  condition. 

The  iron  bath  is  even  more  troublesome  than  brass 
and  less  certain  in  the  production  of  satisfactory  depos- 
its. Owing  to  its  tendency  to  oxidize,  the  bath  must 
i 


50  ELECTROTYPING. 

be  frequently  filtered  to  insure  uniform  deposits.  For 
the  same  reason  it  should  be  kept  under  cover  when 
possible.  The  surface  of  anodes  exposed  should  always 
be  seven  or  eight  times  greater  than  the  cathodes. 


ELECTROTYPING.  51 


CHAPTER  VII. 


AGITATION    OF    BATHS. 


THE  continuous  agitation  of  the  copper  bath  is  of 
great  advantage  to  the  electrotyper,  particularly 
when  rapid  deposition  is  desired.  The  copper  is  more 
evenly  deposited  and  of  better  quality,  the  formation 
of  gas  bubbles  and  also  of  nodules  and  excrescences 
is  largely  prevented,  while  the  annoying  streaks  which 
sometimes  appear  on  the  deposit,  usually  as  the  result 
of  an  excess  of  metal  in  the  solution,  are  seldom  or 
never  seen  in  an  agitated  bath.  But  the  principal 
advantage  may  be  found  in  the  fact  that  much  higher 
current  densities  may  be  utilized,  resulting  in  a  corre- 
sponding increased  rate  of  deposition.  With  a  quiescent 
solution  the  quantity  of  current  which  may  be  employed 
is  limited  to  about  i8  or  20  amperes  per  square  foot ; 
any  excess  of  this  quantity  usually  results  in  a  deposit, 
dark  red  or  black  in  color,  and  rotten,  porous  or  granu- 
lar in  texture.  But  in  an  agitated  bath  these  defects 
disappear.  The  copper  becomes  lighter  in  color,  and 
tough  and  ductile  in  character,  and  these  conditions 
will  not  change  materially  even  when  the  current  density 
is  increased  to  100  amperes  or  more  per  square  foot. 
A  quiescent  solution  is  seldom  of  equal  density 
throughout.     The  heavier  portions  settle  to  the  bottom 


52  KLFXTROTYPING. 

of  the  vat  and  the  lighter  portions  rise  to  the  top,  and 
while  the  density  of  the  bath  may  be  temporarily  equal- 
ized by  occasional  stirring,  there  is  a  continual  tendency 
to  separation.  The  evils  resulting  from  this  lack  of 
homogeneity  have  been  described  in  a  previous  chapter, 
and  the  remedy  for  these  evils  is  continuous  agitation. 
There  are  various  methods  by  which  this  object  may  be 
accomplished.  A  small  propeller  may  be  operated 
near  the  bottom  at  one  end  of  the  vat,  or,  where  sev- 
eral vats  are  employed,  they  may  be  arranged  in  steps 
and  the  solution  permitted  to  flow  through  a  connecting 
pipe  from  the  upper  vat  to  the  next  lower  vat,  and  so 
on  through  the  series. 

Fig.  5  shows  a  depositing  vat  arranged  for  working 
by  the  Englehard  process.  For  electrotyping,  the 
anodes  used  are  about  7  inches  wide  and  i^  inches 
thick,  the  length  being  as  may  be  needed  for  the  work 
in  hand.  They  are  mounted  on  spindles  as  shown, 
and  by  suitable  arrangement  are  rotated  by  power 
while  the  battery  is  in  action,  the  usual  rate  of  speed 
being  about  fifty  revolutions  per  minute.  The  agita- 
tion of  the  solution  insures  thorough  mixture  and  uni- 
form density  ;  friction  between  the  solution  and  the 
moving  anode  clears  its  surface  of  foreign  matter  and 
facilitates  its  rapid  dissolution.  This  also  permits  the 
employment  of  much  greater  electrical  energy  than 
in  vats  as  ordinarily  worked  —  in  fact,  quite  beyond  the 
capacity  of  nearly  every  plating  dynamo  in  use.  The 
inventor  claims  a  current  of  6  or  more  volts  per  vat, 
and  75    to    100   amperes  per   square   foot  of  cathode 


ELECTROTYPING. 


53 


Fig.  5. 


54 


ELFXTROTYPING. 


may  be  used  without  the  least  indication  of  burning 
the  deposit,  which  is  of  finer  quality  than  that  usually 
made  in  the  old  way,  and  the  quantity  of  metal  thrown 
down  is  fully  twice  as  much  in  a  given  time. 

The  Dunton*  method  for  producing  a  circulation  in 
the  solution  is  illustrated  in  Fig.  6.  A  small  centrifu- 
gal pump,   with   a  capacity  of  about   40   gallons    per 


Fig  6. 


minute,  rests  on  the  bottom  of  one  corner  of  the  vat. 
The  solution  is  drawn  in  through  a  strainer  at  a  point 
over  the  center  of  the  wheel,  near  the  bottom  of  the 
vat,  and  discharged  near  the  surface.  In  this  manner 
the  heavier  liquid  is  lifted,  and  by  the  force  of  its  dis- 
charge a  circular  motion  is  imparted  to  the  whole  body. 
It  is  forced  toward  the  end  of  the  tub,  where  it  glances 


ELECTROTYPING.  55 

across,  down  the  other  side,  some  of  it  passing  between 
the  anodes  and  cathodes,  across  the  opposite  end  to  a 
point  nearly  over  the  pump.  The  pvmip  occupies  an 
area  6^  inches  square  by  4  inches  high,  and  is  con- 
structed entirely  of  lead  and  hard  rubber.  Above  the 
solution  the  shaft  ends  in  a  length  of  hardened  steel 
tubing,  which  runs  in  the  upper  bearing  and  carries  the 
driving  gear.  The  two  lower  bearings,  under  the  solu- 
tion, consist  of  flint  glass  bushings  pressed  into  hard 
rubber  jackets,  then  forced  into  the  sleeves  provided  at 
the  top  and  bottom  of  the  pump  casing. 

Fig.  7  illustrates  the  Leetham  apparatus,  which  is 
particularly  suitable  for  electrotyping  solutions.  Agita- 
tion is  effected  by  air  compressed  in  a  reservoir  by  a 
small  double-acting  pump.  The  air  is  forced  into  the 
baths  through  perforated  lead  pipes  which  lie  on  the 
bottom  of  the  vats,  where  they  are  entirely  out  of  the 
way  of  the  work. 

The  perforations  in  the  pipes  are  only  about  one  inch 
apart,  which  insures  thorough  circulation  of  the  solu- 
tion between  the  anodes  and  cathodes. 

The  pressure  is  regulated  by  valves,  and  the  agita- 
tion may  therefore  be  made  more  or  less  violent  at  the 
pleasure  of  the  operator.  On  top  of  the  air  reservoir 
and  connected  with  it  is  a  condensing  chamber  through 
which  the  air  passes  before  it  is  admitted  to  the  vat. 
The  condensing  chamber  is  provided  with  an  inlet  for 
steam.  When  it  is  desired  to  increase  the  temperature 
of  the  bath  or  increase  its  contents  of  water,  steam  is 
admitted  to  the  chamber,  where  it  is  condensed,  and  is 


56 


ELECTROTYPING. 


Fig.  7. 


ELECTROTYPING,  57 

then  conveyed  to  the  solution  through  the  air  pipes. 
This  device  therefore  provides  a  means  for  heating  the 
sohition  and  supplying  it  with  distilled  water  as  well  as 
agitating  it.  Another  obvious  advantage  of  this  appa- 
ratus is  that  one  machine  will  agitate  the  contents  of 
several  vats. 


r)S  ELECTROTYPING. 


CHAPTER  VIII. 

MEASURING    INSTRUMENTS. 

A  CONVENIENT  and  almost  indispensable  measur- 
ing instrument  in  the  electrotype  foundry  is  the 
hydrometer,  or,  as  it  is  popularly  termed,  acid  gauge. 
By  its  aid  the  desired  quantity  of  salts  or  acid  in  the 
bath  may  be  conveniently  measured,  and  the  specific 
gravity  of  any  solution  readily  determined.  The  hydrom- 
eter consists  of  a  glass  tube  with  a  graduated  stem  of 
uniform  diameter,  a  bulb  to  cause  it  to  float  in  the 
liquid,  and  a  weight  to  keep  it  upright  as  it  floats. 
From  the  reading  of  the  scale  at  the  point  which  is  on  a 
level  with  the  liquid  in  which  it  is  floating,  the  density 
of  the  fluid  may  be  ascertained.  In  pure  water  at 
a  temperature  of  60°  Fahr.,  the  hydrometer  sinks 
to  the  zero  mark,  but  by  the  addition  of  salts  or  acid 
having  a  greater  density  than  water,  the  bulb  is  forced 
upward,  and  the  reading  on  the  scale  will  then  indicate 
the  increased  density.  In  making  up  electrotyping 
solutions,  the  hydrometer  is  floated  in  a  vat  partially 
filled  with  water.  Sulphate  of  copper  is  then  dissolved 
in  the  water  until  the  increased  density  of  the  solution 
forces  the   instrument  upward   to  a  reading   which   is 


ELECTROTYPING.  59 

known  to  indicate  the  desired  proportions.  Sulphuric 
acid  is  then  added  to  the  solution  until  the  desired 
quantity  is  denoted  on  the  scale  of  the  instrument.  To 
further  illustrate  :  a  popular  bath  for  nickel-plating  is 
made  by  dissolving  three-fourths  of  a  pound  of  salts  in 
each  gallon  of  water ;  but  instead  of  weighing  the  salts 
and  measuring  the  water  the  same  proportion  may  be 
obtained  by  dissolving  salts  in  any  quantity  of  water 
until  the  hydrometer  scale  registers  7  degrees.  There 
are  two  well-known  makes  of  hydrometers  in  use, 
namely :  the  Baum^  and  the  Twaddle.  Every  degree 
on  the  scale  of  a  Twaddle  hydrometer  represents  .005 
of  a  degree  of  specific  gravity.  Zero  on  the  scale  is 
equivalent  to  i.ooo  specific  gravity.  To  ascertain  by  a 
Twaddle  hydrometer  the  specific  gravity  of  any  liquid 
heavier  than  water,  multiply  the  reading  by  .005  and 
add  1.000.  For  example,  the  reading  on  the  hydrom- 
eter is  60  degrees  :  60  X  .005  =  .300  +  i.ooo  =  1.300, 
the  actual  specific  gravity  of  the  liquid.  The  specific 
gravity  of  a  liquid  may  also  be  easily  ascertained  by 
means  of  a  Baum^  hydrometer  by  a  simple  calculation 
as  follows  :  Subtract  the  reading  from  the  number  144, 
and  divide  the  same  number  by  the  difference.     For 

example,  144  —  50  =  -^  ^  i-532,  the  specific  gravity 

94 
of  a  liquid  registering  50  degrees  on  a  Baume  hydrom- 
eter. 

Instruments  for  measuring  electric  currents  should 
belong  to  the  equipment  of  every  well-ordered  electro- 
typing  establishment.     In  the  early  days  of  the  art  it 


fiO  ELECTROTYPING. 

was  sufficient  to  know  that  a  current  of  some  kind  was 
at  work  and  that  in  due  course  of  time  a  shell  of  suf- 
ficient thickness  would  be  deposited.  It  might  take 
twelve  hours  at  one  time  and  eighteen  at  another,  but  a 
few  hours  more  or  less  was  not  considered  of  serious 
moment.  With  the  modern  electrotyper,  however, 
every  minute  counts,  and  as  a  rule  he  employs  all  the 
current  strength  which  can  be  utilized  without  burning 
the  deposit.  Having  learned  by  experience  what  quan- 
tity may  be  employed  to  advantage,  it  is  of  great  con- 
venience to  be  able  to  measure  the  current  and  by 
means  of  proper  registering  instruments  maintain  the 
pressure  at  the  maximum  point.  Instruments  for  meas- 
uring electricity  are  the  voltmeter  and  the  ammeter. 
The  former  measures  the  tension  and  the  latter  the 
density  of  the  current.  While  the  scientific  electrotyper 
would  find  both  instruments  convenient,  the  ammeter  is 
not  indispensable,  for  the  strength  of  a  current  proceed- 
ing from  a  dynamo  increases  with  the  tension,  and  an 
instrument  which  registers  the  tension  would,  so  far  as 
the  electrotyper' s  necessities  are  concerned,  also  meas- 
ure the  volume.  Assuming  that  one  volt  pressure  is 
sufficient  to  force  a  current  of  12  amperes  per  square 
foot  of  cathode  through  a  solution  of  given  proportions, 
then  with  two  volts  pressure  the  current  strength  would 
be  increased  to  24  amperes  and  three  volts  would  mean 
about  36  amperes  per  square  foot.  If,  therefore,  the 
electrotyper  is  provided  with  a  voltmeter  he  may 
determine  with  sufficient  accuracy  for  his  purpose  the 
strength  of  current  employed. 


ELECTROTYPING.  61 

The  speed  with  which  copper  may  be  deposited 
depends  on  certain  conditions,  but  more  especially  on 
the  density  of  current  employed.  To  reproduce  such 
conditions  at  all  times  it  is  important  that  the  E.  M.  F. 
existing  between  the  anode  and  cathode  should  be 
accurately  measured.  The  ordinary  galvanometer  is 
insufficient  for  this  purpose  because  it  does  not  give  an 
accurate  reading  of  the  tension.  On  the  other  hand,  a 
sensitive  voltmeter  will  indicate  any  loss  of  power  due 
to  slipping  belts,  short  circuits  or  irregularities  of  any 
kind,  and  when  used  in  connection  with  a  switchboard 
will  enable  the  electrotyper  to  accurately  reproduce  the 
conditions  which  he  has  found  by  experience  conducive 
to  success. 

The  switchboard  or  resistance  board  consists  of  a 
number  of  metallic  spirals,  usually  of  German  silver, 
arranged  on  a  board  in  such  a  manner  that  one  or 
more  of  them  may  be  switched  into  the  circuit, 
thus  presenting  more  or  less  resistance,  as  may  be 
desired,  to  the  passage  of  the  current.  The  utility 
of  the  switchboard  may  be  illustrated  as  follows :  sup- 
pose a  tension  of  2j^  volts  is  desired  in  the  bath 
and  that  by  reason  of  slipping  belts  or  other  causes 
the  tension  has  been  reduced  to  2^  volts.  Then  by 
moving  the  handle  of  the  switchboard  one  or  two  but- 
tons a  corresponding  number  of  spirals  will  be  cut  out 
of  the  resistance,  permitting  a  larger  quantity  of  current 
to  enter  the  bath.  Or  suppose  the  load  in  the  bath  be 
much  smaller  than  usual,  or  for  any  other  cause  the  ten- 
sion increases  beyond  the  desired  limit,  a  movement  of 


62  ELECTROTYPING. 

the  switch  handle  ia  the  opposite  direction  will  increase 
the  resistance  by  adding  to  the  number  of  spirals  in  the 
circuit  and  the  tension  will  thus  be  regulated.  The 
wires  connecting  the  voltmeter  with  the  baths  may  be 
arranged  in  such  manner  that  the  tension  in  any  one  of 
a  series  may  be  readily  determined. 


ELECTROTYPING.  63 


CHAPTER   IX. 

PREPARATION    OF   WORK. 

SUCCESS  in  electrotyping  depends  largely  on  care- 
ful attention  to  details,  not  the  least  important  of 
which  is  the  preparation  of  cuts  or  type  forms  for  mold- 
ing. The  finished  electrotype  must  be  perfectly  flat  to 
insure  satisfactory  printing.  If  the  original  form  is 
defective  by  reason  of  imperfect  justification,  high  or  low 
cuts  or  type,  the  defects  will  necessarily  appear  in  the 
electrotype  and  must  finally  be  rectified  at  the  finishing 
bench.  The  truth  of  the  old  adage  '  'A  stitch  in  time 
saves  nine ' '  is  nowhere  better  illustrated  than  in  electro- 
typing.  A  few  minutes'  time  spent  in  making  ready  the 
form  for  molding  frequently  saves  hours  at  the  finishing , 
bench,  particularly  when  a  number  of  duplicate  electro- 
types are  made  from  the  same  form.  For  instance,  a 
broken  or  mashed  type,  unless  discovered  and  replaced 
by  a  perfect  one  before  the  form  is  molded,  will  be  a 
defect  existing  in  every  electrotype  made  from  that  form 
and  must  be  finally  corrected  by  punching  out  the 
defective  letter  and  soldering  in  its  place  a  perfect  type. 
These  defects  are  not  always  the  fault  of  the  electro- 
typer,  but  it  is  nearly  always  difficult  to  convince  the 


64  ELECTROTYPING. 

printer  of  that  fact  unless  a  proof  is  furnished  by  the 
printer  with  the  job. 

Printers'  forms  frequently  consist  of  both  type  and 
cuts,  and  it  often  happens  that  the  cuts  are  lower  or 
higher  than  the  type.  Here  again  a  few  minutes'  time 
spent  in  shaving  down  or  underlaying  the  cuts,  as  the 
case  may  demand,  will  save  much  valuable  time  in  the 
later  operations  of  finishing,  and  will  also  insure  a  better 
electrotype,  for  it  is  obvious  that  if  the  cut  is  low  in  the 
plate  it  must  be  forced  up  to  a  level  with  the  type  by 
punching  or  hammering,  and  it  will  be  plain,  even  to 
the  novice,  that  a  plate  which  has  been  subjected  to 
such  treatment  will  be  less  perfect  than  one  which  has 
been  corrected  in  the  original  and  which,  therefore, 
requires  but  litde  attention  from  the  finisher. 

Usually  better  results  are  obtained  by  the  molder 
from  metal-mounted  cuts  than  when  they  are  mounted 
on  wood,  as  the  wood  bases  are  liable  to  yield  somewhat 
under  pressure  and  will  thus  make  a  shallower  impres- 
sion in  the  molding  composition  than  the  surrounding 
type.  Moreover  there  is  danger  of  losing  something  of 
the  detail  of  the  engraving.  This  is  more  especially 
true  of  half-tone  engravings,  which  should  always  be 
mounted  on  metal  bases. 

Wood  engravings,  when  subjected  to  changes  of  tem- 
perature or  atmospheric  conditions,  sometimes  check  or 
crack.  When  it  is  desired  to  make  an  electrotype  of 
such  an  engraving,  the  checks,  if  not  too  large,  may  be 
closed  by  covering  them  with  strips  of  damp  blotting 
paper  and  then  applying  a  hot  building  iron   to  the 


ELECTROTYPING.  65 

paper  until  it  is  wholly  or  partially  dry.  When  the 
check  has  been  closed  the  mold  should  be  made  at  once 
before  it  has  time  to  open  again. 

Forms  which  are  to  be  electrotyped  should  be  sur- 
rounded by  type-high  beveled  bearers  with  the  beveled 
side  next  the  type.  The  bearers  prevent  the  wax  or 
composition  from  spreading,  and  also  serve  to  protect 
the  face  of  the  electrotype  from  injury  during  the  oper- 
ations of  shaving  and  finishing. 

When  low  leads,  quads  and  furniture  are  used  to 
justify  the  form,  the  larger  blanks  may  be  filled  up  to  the 
shoulders  of  the  type  with  strips  of  wax.  The  wax  will 
adhere  to  the  furniture  sufficiently  to  hold  them  in  place 
when  the  form  is  inverted  on  the  case ;  and,  on  the  other 
hand,  if  the  wax  filling  is  well  brushed  over  with  black- 
lead  after  it  has  been  placed  in  the  blanks,  it  will  not 
adhere  to  the  mold.  Preparing  the  forms  in  this  manner 
will  prevent  undue  displacement  of  the  molding  compo- 
sition and  facilitate  the  later  operations  of  cutting  down 
and  building.  Parts  of  book  pages  or  pages  of  poetry 
should  have  an  inverted  type  placed  in  each  corner  of 
the  page  to  indicate  the  size  of  the  page  and  serve  as  a 
guide  to  the  finisher,  and  title-pages  and  large  blanks 
of  all  kinds  should  have  inverted  letters  so  placed  as 
to  protect  isolated  lines  from  injury  during  the  finishing 
processes. 

All  forms  which  are  to  be  electrotyped  should  be 

securely  locked  in  extra  strong  chases  and  be  perfectly 

justified.     The  type  should  be  squarely  on  its  feet  and 

carefully  planed.     The  pressure  employed  in  molding  is 

5 


66  ELECTROTYPING. 

such  that  unless  great  care  is  taken  to  lock  up  the  forms 
securely  the  wax  will  be  forced  between  the  bodies  of 
the  type,  causing  them  to  spread  and  throwing  them  off 
their  feet.  This  will  result  in  an  imperfect  plate,  and  at 
the  same  time  be  the  cause  of  much  trouble  and  annoy- 
ance owing  to  the  difficulty  of  removing  the  wax  thus 
firmly  imbedded  in  the  form.  Moreover,  unless  the 
form  is  securely  locked,  there  is  danger  that  some  of  the 
types  will  be  drawn  out  of  the  form,  when  it  is  separated 
from  the  mold,  and  lost  or  misplaced. 


ELECTROTYPING.  67 


CHAPTER    X. 


MOLDING. 


THE  most  important  department  of  electrotyping, 
from  the  workman's  point  of  view,  is  the  molding, 
and  it  is  here  that  the  question  of  profit  or  loss  on  a  job 
is  often  determined.  In  some  other  departments  of  the 
foundry  the  work  may  be  slighted  to  some  extent  with- 
out materially  affecting  the  output,  but  carelessness  or 
inefficiency  on  the  part  of  the  molder  always  means 
delay,  extra  expense  for  finishing  inferior  electrotypes, 
and  possibly  a  final  rejection  of  the  job.  A  cheap 
(poor)  molder  is  always  the  most  expensive  man  in 
the  foundry,  for  unless  a  perfect  mold  is  obtained  the 
time  expended  in  later  operations  of  depositing,  casting 
and  finishing  will  be  wasted.  Until  recently  the  mate- 
rial most  generally  employed  for  molding  composition 
was  beeswax,  mixed  with  a  little  crude  turpentine  and 
plumbago.  The  proportions  vary  somewhat,  according 
to  the  ideas  of  the  molder.  A  good  combination  is 
composed  of  pure  beeswax  eighty-five  per  cent,  tur- 
pentine ten  per  cent  and  plumbago  five  per  cent.  If 
the  molding  room  is  very  warm,  about  five  per  cent  of 
burgundy  pitch  may  be  added  with  advantage.  A 
cheaper  material  which  is  now  quite  generally  em- 
ployed is  ozokerite.  Ozokerite  is  a  mineral  wax,  which 
can  hardly  be  distinguished  from  beeswax.     It  has  a 


68  ELECTROTYPING 

high  melting  point,  is  non-adhesive  and  by  most  elec- 
trotypers  is  claimed  to  be  superior  to  beeswax  for  gen- 
eral work.  In  some  instances  gutta-percha  is  employed 
as  a  molding  material,  and  under  proper  conditions  the 
results  obtained  are  very  satisfactory.  The  kind  best 
adapted  for  the  work  is  what  is  known  as  the  unmanu- 
factured but  purified  sheet.  Gutta-percha  takes  a  coat- 
ing of  blacklead  readily,  and  is  impervious  to  the  solu- 
tion. When  used  for  molding  without  pressure,  as  is 
usually  the  case  in  duplicating  steel  engravings  or  arti- 
cles of  a  fragile  nature,  it  is  melted  and  thoroughly 
mixed  with  about  forty  per  cent  refined  lard,  or  it  may 
be  dissolved  in  bisulphide  of  carbon,  and  then  moder- 
ately heated  until  it  is  thin  enough  to  pour. 

A  good  molding  composition  for  certain  purposes 
may  be  made  by  melting  together  one  pound  of  lead, 
^  pound  of  tin,  and  i^^  pounds  of  bismuth.  This 
alloy  melts  at  the  temperature  of  boiling  water,  and 
assumes  a  soft  but  firm  condition  just  before  setting, 
at  which  time  the  impression  should  be  made.  The 
principal  advantage  of  this  composition  is  found  in  the 
fact  that  it  expands  in  cooling,  and  therefore  takes  a 
very  sharp  impression.  An  elastic  composition  recom- 
mended by  Urquhart,  which  may  be  used  for  molding 
an  entire  object  at  one  time,  is  prepared  as  follows: 
Eight  pounds  of  good  glue  is  soaked  in  cold  water 
until  quite  soft.  It  is  then  placed  in  a  glue-pot  and 
mixed  with  two  pounds  of  treacle.  The  whole  is  heated 
and  thoroughly  incorporated  by  stirring;  when  the 
mold  is  not  likely  to  be  roughly  handled,  ^  pound  of 
beeswax  may  be  added  to  the  mixture.  This  material 
is  poured  around  the  prepared  object,  and  when  set 


ELFXTROTYPING.  69 

may  be  cut  open  from  top  to  bottom  and  the  object 
removed ;  the  mold  will  now  sprinj^  into  its  original 
position  and  shape.  The  tendency  of  this  composition 
to  absorb  water  may  be  prevented  by  immersing  the 
mold  in  a  weak  solution  of  bichromate  of  potash  and 
drying  in  the  sun.    An  insoluble  coating  is  thus  secured. 

A  list  of  materials  suitable  for  molding  composition 
might  be  extended  to  include  nearly  any  inelastic  sub- 
stance which  can  be  sufficiently  softened  to  receive  an 
impression  from  type  or  cuts  with  a  reasonable  degree 
of  pressure.  At  this  writing  admirable  results  are 
being  obtained  from  pure  lead  under  the  name  of  the 
Doctor  Albert  process,  a  description  of  which  will  be 
found  in  another  chapter.  However,  there  is  no  mate- 
rial which,  for  general  work,  equals  in  popularity  pure 
ozokerite  or  ozokerite  mixed  with  a  little  beeswax. 
Freedom  from  lumps,  fiber  or  grain  insures  a  perfect 
medium  for  the  production  of  the  finest  lines  and 
shades  of  engraving.  It  may  be  easily  softened  by 
heat  to  the  degree  most  suitable  for  molding  and  will 
not  perceptibly  shrink  in  cooling  or  recover  its  form 
after  receiving  an  impression.  Moreover  it  takes  black- 
lead  readily,  is  unabsorbent  and  may  be  used  over  and 
over  innumerable  times.  In  this  age  of  adulterations 
it  is  not  always  easy  to  obtain  pure  wax,  but  most 
adulterations  may  be  detected.  The  materials  which 
are  most  commonly  mixed  with  wax  are  paraffin,  resin 
and  tallow,  and  the  presence  of  these  substances  may 
be  suspected  if  the  fracture  is  smooth  instead  of 
granular. 

To  prepare  wax  for  molding  it  should  be  melted  in 
a  steam-jacketed  kettle  and  heated  for  several  hours  to 


70  ELFXTROTYPING. 

expel  all  the  moisture.  About  ten  per  cent  of  crude 
turpentine  and  five  per  cent  blacklead  should  then  be 
added  and  thoroughly  incorporated.  Having  been  thus 
prepared  the  wax  is  dipped  out  and  poured  through  a 
strainer  upon  some  shallow  trays  of  brass  or  other 
metal  and  allowed  to  cool.  These  trays,  or  cases,  are 
sometimes  made  of  brass  plates  of  a  convenient  size 
with  the  edges  raised  about  one-fourth  of  an  inch  so  as 
to  form  a  shallow  pan.  Such  cases  are,  however,  quite 
expensive  and  entirely  unnecessary,  as  a  perfectly  flat 
plate  made  of  electrotype  backing  metal  will  serve  the 
purpose  even  better  than  brass,  for  in  the  event  of  its 
becoming  bent  or  warped  it  may  be  easily  straightened 
by  simply  laying  it  on  a  flat  surface  and  planing  it 
down  with  a  hammer  and  block.  A  raised  edge  may  be 
obtained  by  surrounding  the  case  with  wood  or  metal 
strips  of  suitable  height.  It  is  customary  to  place  the 
cases  on  a  stone  or  iron  table  large  enough  to  accom- 
modate several  at  the  same  time  and  located  within 
convenient  distance  of  the  wax-melting  pot.  When  a 
stone  table  is  employed  for  the  purpose  it  should  be 
very  thick,  not  less  than  five  or  six  inches,  in  order 
that  it  may  quickly  absorb  the  heat  from  the  cases  and 
thereby  facilitate  the  cooling  of  the  wax,  otherwise 
much  time  would  be  consumed  in  waiting  for  the  wax 
to  set  sufficiently  to  stand  handling.  Even  a  heavy 
stone  table,  unless  of  extraordinary  size,  will  not  cool 
cases  fast  enough  when  the  volume  of  work  is  consid- 
erable, and  under  such  conditions  it  is  advisable  to 
employ  a  hollow  iron  table  provided  with  water  and 
waste  connections  so  that  a  circulation  of  cold  water 
may  be  maintained  and  the  time  required  to  cool  the 


ELECTROTYPING.  .  71 

cases  reduced  to  the  minimum.  Such  a  table  may  have, 
permanently  secured  to  its  surface  a  strip  of  iron, 
three-eighths  of  an  inch  thick,  extending  entirely 
around  the  outside  edge.  The  flat  cases,  about  one- 
eighth  of  an  inch  thick,  are  then  laid  on  the  table  and 
wax  poured  on  them  until  it  reaches  the  height  of  the 
^-inch  strips.  The  cases  may  be  separated,  if  desired, 
by  strips  of  wood.  After  the  wax  has  set,  the  cases 
are  cut  out  with  a  knife  and  removed  from  the  table, 
and  the  residue  returned  to  the  kettle.  The  iron  table 
may  be  made  still  more  effective  by  providing  it  also 
with  steam  connections,  for  it  often  happens  on  a  cold 
morning  that  the  table  is  too  cold  to  cast  perfect  cases, 
and  considerable  time  is  consumed  in  producing  the 
proper  temperature  by  outside  influences.  In  pouring 
the  wax  on  the  cases  it  is  always  advisable  to  strain  it 
and  thereby  insure  the  exclusion  of  all  dirt  or  foreign 
matter  which  may  have  found  its  way  into  the  melting 
kettle.  Immediately  after  pouring,  a  straight-edge  or 
wire  should  be  drawn  over  the  surface  of  the  cases  to 
remove  any  air  bubbles  which  may  have  formed.  Any 
bubbles  which  do  not  yield  to  this  treatment  may  be 
lightly  touched  with  a  gas  flame.  Neither  wax  nor  com- 
position material  can  be  used  for  molding  until  some 
time  after  it  has  been  cast  in  cases,  or  until  it  has  had 
time  to  cool,  and  it  is  therefore  the  practice  to  cast 
cases  several  hours  in  advance  of  the  time  they  will  be 
required  for  use. 

Molding  presses  operated  by  steam  or  hydraulic 
power  are  usually  provided  with  devices  for  indicating 
the  depth  of  impression  made  in  the  wax,  or  with  auto- 
matic stops  for  shifting  the  belt  when  the  impression 


72  ELRCTROTYPINO. 

has  reached  a  predetermined  depth.  Such  devices  are 
effective  only  when  the  wax  cases  are  all  of  the  same 
thickness  and  of  imiform  temperature.  The  tempera- 
ture of  the  wax  determines  its  degree  of  plasticity,  and 
the  suitable  degree  is  indicated  when  the  wax  will  yield 
under  pressure  of  the  thumb.  The  ability  to  judge  the 
correct  temperature  comes  with  experience,  and  can  be 
acquired  in  no  other  way. 

By  exercising  due  care  to  fill  the  cases  level  with 
the  bearers  which  surround  them,  the  waxcaster  may 
produce  cases  reasonably  uniform  as  to  thickness ;  but 
to  insure  absolute  accuracy  they  should  be  passed 
through  a  wax-shaving  machine,  which  not  only  in- 
sures uniformity  but  also  removes  any  dirt  or  dust 
which  may  have  become  attached  to  the  wax  while  in 
a  liquid  or  semi-liquid  state. 

When  wax  cases  are  cast  several  hours  in  advance 
of  their  use  and  have  become  cold  and  brittle,  it  is 
necessary,  before  molding,  to  restore  them  to  a  plastic 
condition,  as  any  attempt  to  mold  in  cold  wax  would  be 
not  only  dangerous  alike  to  press  and  form,  but  would 
inevitably  result  in  failure.  The  wax  is  sometimes 
softened  by  laying  the  cases  on  a  steam-heated  table, 
such  as  is  illustrated  in  Fig.  8,  first  placing  some  strips 
of  wood  on  the  table  to  protect  the  back  of  the  case 
from  excessive  heat.  Unless  so  protected,  the  wax 
next  the  case  would  become  much  softer  than  the  face,' 
and  the  result  of  molding  from  a  case  thus  unevenly 
heated  would  almost  certainly  be  concaved  faces  in  the 
reproduced  type  and  cuts.  Even  when  great  care  is 
observed  in  warming  the  cases,  it  sometimes  happens 
that  this  defect  occurs  in  the  electrotype,  and  for  this 


ELECTROTYPING. 


7;? 


reason  as  well  as  to  avoid  delay  it  is  advisable  to  keep 
the  cases  in  a  box  moderately  heated  by  steam  or  hot 
air  where  they  will  be  gradually  brought  to  nearly 
the  proper  temperature  for  molding.  They  will  then 
require  an  exposure  of  but  a  few  moments  on  the 
steam  table  to  make  them  sufficiently  plastic.     Instead 


Fig.  8. 
Electrotypers'  Wax  Kettle  and  Table. 


of  a  box,  a  number  of  pigeonholes  may  be  constructed 
about  two  feet  above  the  steam  table  in  such  a  manner 
that  the  cases  may  rest  on  their  edges  in  a  vertical 
position,  and  the  hot  air  arising  from  the  steam  table 
permitted  to  circulate  between  them. 

Having  warmed  the  case  until  the  wax  will  take  an 


74  ELECTROTYPING. 

impression  of  the  thumb,  it  is  given  a  thorough  coating 
of  molding  graphite,  which,  when  properly  applied, 
prevents  the  wax  from  spreading.  Graphite  should 
also  be  applied  to  the  form,  rubbing  it  in  thoroughly 
with  a  brush  in  order  to  prevent  the  type  or  cuts  from 
adhering  to  the  wax. 

The  form  is  now  placed  on  the  apron  of  the  mold- 
ing press  and  the  case  inverted  upon  it,  or  if  the  form 
is  small  the  operation  may  be  reversed  and  the  form 
inverted  upon  the  case.  In  either  event  two  or  three 
sheets  of  heavy  strawboard  should  be  placed  between 
the  back  of  the  case  and  the  press  to  prevent  too  sud- 
den chilling  of  the  wax.  Having  been  thus  prepared, 
the  form  and  case  with  its  strawboard  backing  are  slid 
under  the  head  of  the  molding  press  and  pressure 
applied  until  sufficient  depth  of  impression  has  been 
obtained  in  the  wax,  when  the  form  and  mold  should 
be  carefully  separated  and  examined. 

It  will  sometimes  be  found  necessary  to  take  a  sec- 
ond impression  in  order  to  obtain  a  perfect  mold,  and 
in  such  cases  it  is  obvious  that  the  utmost  care  must  be 
exercised  to  prevent  a  doubled  impression.  To  provide 
for  such  contingencies,  forms  which  are  to  be  electro- 
typed  should  be  imposed  in  such  a  manner  as  to  leave 
an  opening  between  the  sections  of  furniture  at  two  of 
the  corners  of  the  chase,  that  the  molder,  when  setting 
the  form  the  second  time,  may  accurately  locate  the 
first  impression. 

When  a  large  number  of  duplicates  are  required 
from  one  form  it  is  customary  to  prepare  a  sufficient 
number  of  electrotype  patterns  to  fill  a  chase  and  there- 
after mold  from  the  patterns  instead  of  the  original 


ELECTROTYPING,  75 

form.  When  the  patterns  are  carefully  prepared  no 
building-  will  be  required  on  the  molds,  and  much  of 
the  labor  of  finishing  will  also  be  saved. 

The  operation  of  the  molding  press  is  sufficiently 
explained  by  the  illustrations  Figs.  9  and  10.  With 
the  exception  of  the  hydraulic  press  the  principle  by 


Fig.  9. 
Electrotypers'  Hand  Molding  Press. 

which  pressure  is  applied  is  the  same  in  all  molding 
presses  —  a  toggle  joint  operated  by  a  screw.  In  the 
hand  press  the  screw  terminates  in  a  hand  wheel  whose 
spokes  extend  beyond  the  rim  of  the  wheel  to  provide 
a  convenient  means  of  applying  power.  The  screw  in 
a  power  press  terminates  in  a  large  gear  wheel  which 
is  engaged  by  a  pinion  driven  by  steam  power. 


70  .  Ki.iarrkoTvi'iNc. 

The  press  illustrated  in  Fig.  lo  is  provided  with  an 
indicator  consisting  of  a  finger  and  graduated  dial,  by 
means  of  which  uniformity  in  depth  of  impression  may 
be  obtained.  The  indicator  is  particularly  useful  when 
two  or  more  impressions  are  required,  for,  having 
noted  the  location  of  the  finger  on  the  dial  plate  at  the 


Fig.  io. 

Electrotypers'  Power  Molding  Press. 

completion  of  the  first  impression,  it  is  an  easy  matter 
to  determine  the  depth  of  the  second. 

In  connection  with  the  operation  of  the  molding 
press  mention  may  be  made  of  a  fact  not  always  recog- 
nized by  molders,  which  is,  that  the  greatest  power 
exerted  by  a  toggle  joint  occurs  just  before  the  toggles 


ELECTROTYPING.  77 

reach  a  perpendicular  position.  The  amount  of  pack- 
ing placed  under  the  case  is  sometimes  so  excessive 
that  the  toggles  never  reach  the  point  of  highest  effi- 
ciency, and  therefore  more  or  less  power  is  unneces- 
sarily expended  in  producing  the  impression.  While 
this  is  of  no  particular  moment  in  the  case  of  the  steam 
press,  except  as  it  throws  a  heavy  strain  on  the  yoke,  a 
proper  adjustment  of  the  packing  would  save  consid- 
erable hard  labor  to  the  operator  of  the  hand  press. 


78  ELECTROTYPING. 


CHAPTER  XL 

BUILDING. 

MOLDING  a  form  or  pattern  naturally  causes  more 
or  less  displacement  of  wax,  which  is  forced  up 
around  the  edges  of  the  form  and  between  the  cuts  or 
type,  or  wherever  there  is  an  opening,  however  small. 
Before  proceeding  to  metallize  the  mold,  it  is  necessary 
that  these  displacements  shall  be  cut  down  to  a  uniform 
level,  for  it  would  not  only  be  difficult  to  metallize,  by 
the  usual  methods,  a  mold  whose  surface  consists  of 
knobs  and  protuberances  of  uneven  heights,  but  it 
would  also  be  impossible  to  cast  the  electrotype  plate 
within  the  limits  of  the  thickness  usually  required  for 
printing  purposes,  for  every  protuberance  on  the  mold 
would  necessarily  involve  a  corresponding  depression  in 
the  shell;  and  inasmuch  as  the  shell  must  be  backed 
with  metal  and  entirely  covered  thereby,  the  thickness 
of  the  finished  electrotype  plate  could  not  be  less  than 
the  highest  point  of  the  shell.  As  a  rule,  electrotypes 
are  made  not  more  than  one  pica  in  thickness,  and  the 
lowest  depression  in  the  electrotype  where  blank  spaces 
occur  must  obviously  be  somewhat  less  than  a  pica  in 
depth. 


ELECTROTYPING.  79 

For  the  purpose  of  cutting  down  the  mold  a  wax 
knife  (Fig.  ii)  of  special  design  is  employed.  The 
mold  and  the  knife  should  be  warm,  and  the  knife  must 
be  occasionally  heated  over  a  gas  jet  or  stove.  The  dis- 
placed wax  is  removed  by  a  shaving,  outward  cut  of  the 
knife,  taking  care  not  to  cut  too  deep  into  the  mold. 


Fig.  II.— Wax  Knife. 


The  operation  requires  some  practice,  but  is  easily 
accomplished  if  the  knife  blade  is  kept  warm  ;  other- 
wise there  would  be  danger  of  breaking  down,  or  dis- 
torting the  walls  of  the  cavities  of  the  mold,  in  which 
case  the  later  operation  of  blackleading  or  metallizing 
the  mold  would  be  rendered  difficult  if  not  impossible. 
Even  a  sharp,  warm  knife  will  leave  the  edges  of  the 
walls  more  or  less  ragged,  but  these  edges  may  be  ren- 
dered smooth  and  rounded  by  passing  rapidly  over  the 
mold  a  lighted  gas  jet  attached  to  a  rubber  hose. 

After  the  cutting-down  process,  the  operator  should 
go  carefully  over  the  mold  with  a  sharp-pointed  tool  and 
pick  out  any  shavings  or  particles  of  wax  which  may 
have  become  lodged  in  the  indentations. 

The  mold  should  now  present  a  reasonably  smooth 
surface,  all  the  high  places  caused  by  displacement  hav- 
ing been  cut  down  to  a  uniform  level,  which  leaves  the 
indentations  in  the  mold  from  ^^  to  ^^  of  an  inch  deep. 


80  ELECTROTYPING. 

If  the  mold  has  been  made  from  a  soHd  type  form,  it 
may  now  be  metaUized  and  prepared  for  the  depositing 
vat;  but  if  made  from  an  open  form,  the  blanks  between 
the  printing  surfaces  must  be  raised  in  order  to  produce 
a  depression  in  the  electrotype  and  thus  eliminate  all 
possibility  of  smutting  in  printing.  Unless  the  blank  is 
raised  or  built  up  in  the  mold,  it  would  be  necessary  to 
deepen  the  depression  in  the  electrotype  by  routing  or 
chiseling,  which  is  a  much  more  expensive  operation 
than  building,  particularly  when  a  number  of  duplicates 
are  required  from  one  pattern.  Building  is  an  operation 
requiring  a  steady  hand  and  a  quick  eye  as  well  as  a 
skill  which  comes  from  long  practice.  The  tools  em- 
ployed are  a  building  iron  (Fig.  12),  a  small  gas  stove 


Fig.  12.— Building  Iron. 

and  a  strip  of  wax.  The  building  iron  is  a  smooth, 
cone-shaped  block  of  copper,  about  two  inches  long,  one 
inch  in  diameter  at  one  end  and  tapering  to  a  sharp 
point  at  the  other,  with  a  handle  eight  or  ten  inches  in 
length  inserted  in  the  side.  Several  of  these  irons 
should  be  provided  in  order  that  while  one  is  in  use  the 
others  may  be  heating.  To  build  up  a  blank  in  the 
mold,  the  operator  takes  a  hot  iron  in  one  hand  and  a 
strip  of  wax  in  the  other,  and,  holding  the  point  of  the 
iron  over  and  close  to  the  blank  which  is  to  be  raised, 


ELECTROTYPING. 


81 


touches  the  iron  Hghtly  with  the  strip  of  wax,  which 
instantly  melts  and  runs  down  the  iron  onto  the  mold. 
If  the  blank  is  large,  the  wax  is  held  in  contact  with  the 
iron  while  it  is  moved  over  the  space  back  and  forth 
until  entirely  covered  and  built  up  to  the  required  height. 

Care  must  be  -taken  not  to  get  the  iron  too  hot,  for 
in  that  case  the  wax  would  be  made  too  thin  and  would 
not  chill  quick  enough  by  contact  with  the  mold,  but 
would  run  off  from  the  blank  and  into  the  indentations  of 
the  mold.  It  is  always  advisable  to  test  the  heat  of  the 
iron  by  running  some  wax  onto  the  edges  of  the  mold 
where  no  damage  can  result.  Before  blackleading  or 
metallizing  the  mold  it  is  also  necessary  to  provide 
places  of  contact  for  the  electrical  connections.-  This 
may  be  done  in  various  ways.  The  simplest  method  is 
to  provide  two  pieces  of  copper  wire,  about  ts  of  an  inch 
in  diameter  and  six  or  seven  inches  longer  than  the  case. 
One  end  of  each  wire  should  be  turned  over  to  form 
hooks  by  means  of  which  the  case  may  be  suspended 
from  the  cross  rods  of  the  depositing  vat.  The  wires 
are  heated  by  dipping  them  in  the  metal  pot  or  in  any 
convenient  manner,  and  are  then  laid  on  the  case,  one 
on  each  side  of  the  mold,  where  they  become  embedded 
by  melting  a  channel  for  themselves  in  the  wax. 

Additional  security  is  obtained  by  covering  over  the 
wires  with  wax  by  means  of  the  building  iron.  This 
method  of  providing  electrical  connection  with  the  mold 
is  simple  and  reasonably  secure,  if  the  case  is  not  too 
heavy ;  but  a  better  method  consists  in  substituting  for 
the  wires  strips  of  thin  sheet  copper  from  one-half  to  one 
6 


82  ELECTROTYPING. 

inch  in  width.  These  strips  are  not  designed  to  sustain 
the  weight  of  the  case,  but  simply  to  act  as  conductors, 
and  for  this  purpose  are  superior  to  wires,  because  they 
assure  a  better  contact  with  the  cross  rods.  When  this 
connection  is  employed,  the  weight  of  the  case  is  sus- 
tained by  S-hooks,  one  end  of  which  is  passed  through 
a  hole  in  the  case,  and  the  other  end,  which  should  be 
insulated,  hooked  over  the  cross  rod. 

There  are  several  other  methods  of  making  elec- 
trical connections  with  the  molds  which  are  valuable 
chiefly  as  time-savers.  One  of  them  is  shown  in  the 
illustration.  A  piece  of  copper  or  brass  is  melted  into 
the  mold  near  the  top  and  makes  contact  with  a  portion 
of  the  hook  which  suspends  the  case  from  the  cross 
rod  of  the  bath. 


ELECTROTYPING.  83 


CHAPTER   XII. 


METALLIZING. 


THE  utility  of  electrotyping  in  its  early  days  was 
restricted  to  the  reproduction  of  medals  or  other 
metallic  objects  which  were  conductors  of  electricity, 
but  in  1840  Mr.  Murray  discovered  that  nonmetallic 
objects  could  be  made  conductive  by  applying  to  their 
surface  a  film  of  graphite  (blacklead),  and  to  this  dis- 
covery is  largely  due  the  successful  application  of  elec- 
trotyping to  the  copying  and  duplication  of  engravings 
and  type  forms.  Only  the  purest  grades  of  graphite 
containing  from  95  to  99  per  cent  of  carbon  are  used 
for  metallizing.  For  this  purpose  it  is  ground  to  a 
seemingly  impalpable  powder,  but  under  the  microscope 
it  is  found  to  consist  of  minute  flakes.  To  metallize  or 
render  conductive  a  nonmetallic  object,  it  is  essential 
that  these  flakes  shall  lie  flat  upon  it  like  the  scales  of  a 
fish,  overlapping  each  other  and  forming  a  continuous 
and  unbroken  metallic  covering  for  the  object.  Such  a 
surface  can  be  obtained  only  by  brushing  or  otherwise 
forcing  the  flakes  into  the  position  described,  which  will 
incidentally  give  to  the  object  a  bright  polish.  Black- 
leading  is  sometimes  accomplished  by  means  of  a  pump 


84  ELECTROTYPING. 

or  air  blast,  as  will  be  hereafter  described,  but  the  usual 
method  is  to  apply  the  graphite  with  a  soft  brush  of 
camel's  or  badger  hair,  either  by  hand  or  with  a  black- 
leading  machine.  For  blackleading  by  hand  a  camel' s- 
hair  brush  is  preferred.  With  this  instrument  the 
graphite  is  brushed  back  and  forth  over  the  mold  until  a 
bright  polish  is  obtained,  and  until  it  is  certain  that  no 
spot,  however  small,  has  been  neglected.  If  so  much 
as  a  punctuation  point  fails  to  receive  the  proper  polish, 
copper  will  not  deposit  thereon,  and  a  hole  in  the  shell 
will  result. 

Blackleading  by  hand  is  a  slow  and  disagreeable 
task,  and  is  seldom  practiced  in  American  foundries,  a 
blackleading  machine  being  considered  essential  even 
in  the  smallest  establishments.  Fig.  13  illustrates  a 
blackleader  which  is  a  type  of  the  machines  in  general 
use  at  the  present  time.  While  there  are  variations  in 
the  mechanical  movements  of  different  machines,  the 
essential  features  are  a  vibrating  brush  or  brushes,  and  a 
reciprocating  bed  to  carry  the  molds  back  and  forth 
under  the  brushes.  The  apparatus  is  all  inclosed  in  a 
tight  box  which  confines  and  prevents  waste  of  graph- 
ite. After  the  mold  has  been  built  up  and  prepared  as 
previously  described  it  is  placed  on  the  bed  of  the 
blackleader  and  covered  thickly  over  with  graphite. 
When  the  machine  is  started  the  molds  travel  slowly 
back  and  forth  while  the  rapidly  vibrating  brushes  soon 
effect  the  necessary  polish.  The  time  required  to  prop- 
erly blacklead  a  mold  depends  upon  the  nature  of  the 
work  and  the  speed  at  which  the  brushes  are  operated. 


ELECTROTYPING. 


85 


A  mold   of  a  type   form    requires    considerable   more 
brushing  than  a  flat  engraving  because  of  the  minute 


Fig.  13.—  Blackleader. 


indentions  made  by  the  punctuation  points,  etc.     With 
a  double-brush  machine  running  at  about  600  revolu- 


86  ELECTROTYPING. 

tions  per  minute,  a  good  polish  is  usually  obtained  in 
from  five  to  ten  minutes. 

A  disagreeable  feature  of  blackleading  is  the  flying 
dust,  which  cannot  be  wholly  confined  and  which  even- 
tually covers  everything  in  the  molding  room,  including 
the  workmen.  This  annoyance  is  minimized  by  the  use 
of  the  inclosed  blackleading  machine  but  not  entirely 
eliminated.  On  this  account  the  wet  process  of  black- 
leading  is  sometimes  preferred.  This  method  was 
invented  and  patented  by  Mr.  Silas  P.  Knight  in  1872. 
By  this  process  the  graphite  is  mixed  with  water  to  the 
consistency  of  thin  cream  and  by  means  of  a  rotary  force 
pump  is  discharged  with  considerable  force  upon  the 
mold  through  a  traveling  rose  nozzle,  the  entire  appara- 
tus being  confined  in  a  water-tight  box.  In  another 
form  of  wet  blackleader  the  emulsion  of  graphite  is 
forced  over  the  mold  by  a  paddle  wheel  which  revolves 
in  the  liquid.  The  blades  of  the  wheel  consist  of 
badger-hair  brushes  which  come  lightly  in  contact  with 
the  mold  and  assist  in  producing  the  necessary  polish. 
The  wet  process  is  said  to  be  entirely  satisfactory,  but 
for  some  reason  has  never  come  into  general  use. 

Various  attempts  have  been  made  to  perform  the 

operation  of  blackleading  by  means  of  a  blower  or  air 

blast,  and  several  patents  have  been  issued  for  machines 

with  this  design.     Fig.  14  illustrates  a  machine  which 

combines  both  the   air-blast   and  brush   features.     Air 

from  the  pressure   blower  (on    the  floor,   back  of  the 

machine)  passes  through  tubes  in  the  horizontal  cylinder 

(above  the  machine)  and  is  discharged  through  a  narrow 
6 


ELECTROTYPING. 


87 


slot  extending  across  the  table  and  close  to  the  mold  ; 
water  circulating  outside  the  tubes  reduces  the  tempera- 


FiG.  14.— Combination  Blackleading  Machine. 

ture  of  the  compressed  air,  so  the  machine  may  be  oper- 
ated continuously — even  in  the  summer  —  without  dan- 
ger of  injury  to  wax   molds.     At  the  bottom  of  the 


88  ELECTROTYPING. 

machine  there  is  a  shallow  drawer  with  a  gauze  bottom 
through  which  the  air  passes  to  the  blower  ;  the  gauze 
retains  particles  of  wax  and  other  substances  likely  to 
obstruct  the  free  passage  of  air  through  the  slot.  How- 
ever, should  the  slot  become  clogged,  by  removing  the 
plate  on  the  front  of  the  machine  the  workman  can 
obtain  access  to  the  wind  chest  and  may  easily  clear 
away  any  obstruction.  By  a  glance  at  the  mercury 
gauge,  on  the  top  of  the  machine,  the  operator  can  see 
whether  the  air  pressure  is  as  it  should  be.  The  brush, 
which  is  of  badger  hair,  is  located  just  back  of  the  wind 
chest  and  actuated  from  a  shaft  supplied  with  a  tight 
pulley,  so,  whenever  desired,  the  brush  may  be  stopped. 
The  distance  of  the  brush  from  the  table  is  adjustable. 

In  operation  the  workman  lifts  the  cover,  at  front, 
which  is  held  raised  by  a  hook  shown  at  the  left  side, 
lays  the  cases  to  be  leaded  on  the  table,  which  is  33  by 
22  inches,  lowers  the  cover,  and  starts  the  machine  by 
pulling  the  handle  on  the  right  until  a  pawl  drops  into  a 
notch  in  the  rod  ;  he  then  adjusts  the  stop  motion  so 
the  table  will  make  one,  two  or  three  trips  forward  and 
back;  when  these  have  been  completed  the  pawl  will  be 
detached  automatically  from  the  rod,  and  the  spring  on 
the  countershaft  carry  the  belt  on  the  loose  pulley,  stop- 
ping the  machine.  It  is  claimed  by  the  manufacturers 
that  a  tableful  of  molds  may  be  metallized  in  one 
minute. 

After  the  mold  has  been  blackleaded,  it  must  be 
thoroughly  freed  from  the  loose  graphite  which  would 
otherwise  remain  in  the  depressed  portions,  particularly 


ELECTROTYPING.  89 

in  the  smaller  indentations  made  by  punctuation  points 
and  leaders,  and  cause  defective  shells.  The  removal 
of  the  superfluous  graphite  may  be  effected  by  a  hand 
bellows,  but  in  large  establishments  a  rotary  fan  opera- 
ted by  power  is  sometimes  employed.  A  still  better 
method  consists  in  taking  the  air  through  a  tube  from 
a  reservoir  in  which  it  has  been  compressed  by  an  air 
pump.  By  this  method  sufficient  pressure  to  thor- 
oughly blow  out  the  mold  is  assured.  From  such  a 
reservoir  additional  tubes  may  be  extended  to  the 
molding  presses,  and  utilized  to  blow  the  loose  graphite 
from  the  molds  as  may  be  necessary  during  the  opera- 
tion of  molding. 

By  the  process  of  blackleading,  the  case  is  rendered 
conductive  over  its  entire  surface,  and  should  it  be  sus- 
pended in  the  bath  without  further  preparation,  it  would 
receive  a  deposit  of  copper  not  only  upon  the  mold  but 
upon  the  margin  of  wax  surrounding  the  mold,  and 
upon  the  back  of  the  case.  To  restrict  the  action  of 
the  current  to  the  surface  upon  which  a  deposit  is 
desired,  the  remaining  portion  is  painted  out  with  hot 
wax  or  varnish,  or  its  conducting  surface  is  destroyed 
by  passing  lightly  over  it  a  hot  building  iron.  The 
conductivity  of  graphite  is  only  .07  of  one  per  cent  as 
compared  with  pure  copper,  100  per  cent,  and  the 
action  of  the  electric  current  on  a  blackleaded  mold  is 
therefore  very  slow  until  covered  with  a  coating  of  cop- 
per, when  deposition  proceeds  rapidly.  To  give  the 
mold  a  better  conducting  surface  than  is  provided  by 
the  graphite,  and  thus  facilitate  immediate  action  of  the 


90  ELECTROTYPING. 

current  over  its  entire  surface,  it  is  customary  to  precipi- 
tate a  film  of  copper  on  the  mold  before  placing  it  in 
the  bath.  This  preliminary  coating  of  copper  is  pro- 
duced by  pouring  on  the  mold  a  solution  of  sulphate  of 
copper  of  about  i6°  Baum6,  and  covering  it  with  a 
sprinkling  of  iron  filings.  With  a  badger-hair  brush 
the  filings  are  lightly  distributed  over  the  mold  until 
thoroughly  wet,  when  they  take  up  the  acid  in  the  solu- 
tion, and  the  copper  thus  set  free  is  precipitated  in  a 
bright  film  on  the  mold.  If  any  portions  of  the  mold 
fail  to  take  the  coating  the  operation  is  repeated.  Par- 
ticular care  is  observed  to  avoid  scratching  the  mold 
with  the  iron  filings. 

Flat  molds  such  as  are  made  for  the  production 
of  copper  printing  plates  may  be  readily  and  effectively 
metallized  by  either  of  the  methods  previously  described, 
but  for  the  production  of  nickel  electrotypes  or  the 
reproduction  of  irregular  shaped  objects  such  as  stat- 
uary, or  art  work  of  various  kinds  having  undercut  or 
deep  portions,  recourse  must  be  had  to  what  is  called 
metallizing  by  the  wet  way.  While  this  class  of  work 
is  not  strictly  in  the  line  of  commercial  electrotyping 
it  is  sufficiently  analogous  to  deserve  mention.  The 
processes  to  be  described  are  recommended  by  such 
practical  writers  as  Langbein,  Urquhart  and  Watt. 
Gutta-percha  or  wax  molds  have  their  surfaces  rendered 
conductible  by  the  following  plan  :  Take  equal  parts 
of  albumen  (white  of  egg)  and  a  saturated  solution  of 
common  salt,  and  apply  the  mixture  to  the  object  to  be 
coated  by  means  of  a  soft  brush.     Then  dry  the  compo- 


ELECTROTYPING.  91 

sition  thoroughly.  Now  make  a  strong  solution  of 
nitrate  of  silver  and  dip  the  mold  into  it  for  a  few  min- 
utes and  dry  again.  Expose  the  mold  to  a  strong  light 
until  it  becomes  quite  black.  The  mold  is  then  to  be 
dipped  into  a  saturated  solution  of  sulphate  of  iron, 
when  a  layer  of  metallic  silver  will  be  formed  upon 
which  a  deposit  of  copper  may  readily  be  obtained. 
The  mold  should  be  rinsed  when  taken  from  the  sul- 
phate of  iron  solution  and  connecting  wire  attached  to 
it,  when  it  may  at  once  be  placed  in  the  depositing  bath. 

Another  method  of  metallizing  is  as  follows:  Dis- 
solve a  piece  of  phosphorus  in  two  drams  of  bisul- 
phide of  carbon,  stir  in  two  drams  of  benzine  and  a 
drop  or  two  of  sulphuric  ether;  pour  the  whole  into 
half  a  pint  of  alcohol  and  wash  the  surface  of  the  mold 
with  this  mixture  twice,  allowing  it  to  dry  after  each 
application. 

The  silver  solution  is  made  by  dissolving  one  dram 
twenty  grains  of  nitrate  of  silver  in  a  mixture  of  half 
a  pint  of  alcohol  and  one  dram  of  acetic  acid.  The 
mold  is  thoroughly  floated  once  with  this  solution  and 
allowed  to  dry  spontaneously. 

Another  and  simpler  method  of  rendering  the  mold 
conductive  may  be  described  as  follows :  Dissolve  phos- 
phorus in  pure  alcohol  until  a  strong  solution  is 
obtained  and  wash  the  mold  with  the  mixture.  The 
silver  solution  is  prepared  by  dissolving  nitrate  of 
silver  in  aqueous  ammonia  to  saturation.  It  is  to  be 
poured  evenly  over  the  mold  and  allowed  to  float  over 
it  for  a  few  minutes.     The  solution  is  poured  off  and 


92  ELFXTROTVPING. 

the  mold  allowed  to  become  partly  dry,  when  it  is  again 
floated  with  the  mixture.  Spots  that  do  not  appear  to 
take  the  solution  readily  should  be  wetted  with  it  by 
means  of  a  soft  brush. 

Still  another  process  is  as  follows:  Apply  with  a 
brush  upon  the  mold  a  not  too  concentrated  solution  of 
nitrate  of  silver  in  a  mixture  of  equal  parts  of  distilled 
water  and  ninety  per  cent  alcohol.  When  the  coat  is 
dry,  expose  it  in  a  closed  box  to  an  atmosphere  of  sul- 
phureted  hydrogen.  The  latter  converts  the  nitrate  of 
silver  into  sulphide  of  silver,  which  is  a  good  conductor 
of  the  current.  For  the  production  of  the  sulphureted 
hydrogen,  place  in  the  box,  which  contains  the  mold  to 
be  metallized,  a  porcelain  plate  or  dish  filled  with  dilute 
sulphuric  acid  (i  acid  to  8  water)  and  add  five  or  six 
pieces  of  iron  pyrites  the  size  of  a  hazelnut.  The 
development  of  gas  begins  immediately  and  the  box 
should  be  closed  with  a  well-fitting  cover  to  prevent 
inhaling  the  poisonous  gas;  if  possible,  the  work  should 
be  done  in  the  open  air  or  under  a  well-drawing  chim- 
ney. The  formation  of  the  layer  of  sulphide  of  silver 
requires  but  a  few  minutes,  and,  if  not  many  molds 
have  to  be  successively  treated,  the  acid  is  poured  off 
from  the  iron  pyrites  and  clean  water  poured  upon  the 
latter  so  as  not  to  cause  useless  development  of  gas. 

For  coppering  leaves,  plants,  flowers,  etc.,  dissolve 
five  parts  (by  weight)  of  wax  in  five  of  warm  oil  of 
turpentine,  and  add  to  the  solution  a  mixture  of  five 
parts  of  phosphorus,  one  of  gutta-percha  and  five  of 
asphalt  in   120  bisulphide  of  carbon.     When  both  are 


ELECTROTYPING.  93 

thoroughly  mixed,  add  to  the  whole  a  solution  of  four 
parts  (by  weight)  of  guncotton  in  sixty  of  alcohol  and 
sixty  of  ether,  and,  after  a  thorough  shaking,  allow  to 
settle.  The  next  day  pour  off  the  clear  solution  from 
the  sediment,  when  the  solution  can  at  once  be  used. 
A  French  process  for  metallizing  leaves,  etc.,  con- 
sists in  immersing  them  in  iodized  collodion  composed 
of  forty  per  cent  alcohol,  40  cubic  centimeters;  ether, 
60  cubic  centimeters;  potassium  iodide,  i  gram;  gun- 
cotton,  I  gram.  Allow  the  leaves,  etc. ,  to  dry  so  that 
a  firmly  adhering  layer  is  formed;  then  immerse  them 
in  a  solution  of  ten  parts  (by  weight)  of  nitrate  of  sil- 
ver in  100  of  water,  whereby  a  layer  of  iodide  of  silver 
is  formed.  Now  expose  the  article  thus  treated  for 
some  time  to  the  light,  and  then  immerse  it  in  the 
reducing  fluid  consisting  of  water,  500  parts;  green 
vitriol,  25  parts,  and  acetic  acid,  25  parts.  The  reduc- 
tion of  silver  proceeds  rapidly  and  the  articles  are  soon 
ready  for  coppering.  Instead  of  the  iodized  collodion, 
a  mixture  of  equal  parts  of  white  of  egg  and  solution 
of  common  salt  may  be  used. 


94  ELECTROTYPING. 


CHAPTER  XIII. 

THE   CONDUCTORS. 

THE  electrodes  and  all  connections  between  the 
dynamo  and  the  molds  or  anodes  should  be  of 
copper  and  should  be  amply  large  to  conduct,  without 
heating,  the  strongest  current  practicable  to  use  in  the 
depositing  process.  It  should  be  remembered  that  the 
generation  of  the  electric  current  requires  power,  and 
that  a  portion  of  the  power  is  always  expended  in  over- 
coming resistance,  and  is,  so  far  as  its  effect  on  the  work 
is  concerned,  wasted.  It  is  obvious,  therefore,  in  the 
interest  of  economy,  that  due  precaution  should  be 
observed  to  provide  both  in  the  conductors  and  in  the 
bath  a  path  of  minimum  resistance.  A  barrel  of  water 
would  run  out  of  an  inch  bunghole  in  a  very  few  min- 
utes, while  it  would  take  a  tremendous  pressure  to  force 
the  same  quantity  of  water  in  the  same  time  through  a 
gimlet  hole.  In  the  same  way  a  current  of  several 
hundred  amperes  will  flow  readily  through  a  large  rod, 
when  the  attempt  to  force  the  same  current  through  a 
small  wire  would  result  in  overheating  the  wire  and  the 
dynamo,  with  a  consequent  waste  of  power.  ' '  The 
development  of  heat  in  the  conductors  or  the  solution  is 
proportional  to  its  resistance  and  is  proportional  to  the 


ELECTROTYPING.  95 

square  of  the  strength  of  the  current.  Hence,  the 
development  of  heat  will  be  the  greater,  the  smaller  the 
cross-section  of  the  conductor  and  its  conducting  capac- 
ity are,  and  the  larger  the  quantity  of  current  which 
passes  through  it." 

The  size  of  the  conducting  rods  required  for  electro- 
typing  depends,  therefore,  on  the  quantity  of  current  to 
be  employed  at  one  time,  which  may  be  estimated  with 
sufficient  accuracy  by  multiplying  the  area  of  the  cath- 
odes in  square  feet  by  the  number  of  amperes  required 
to  deposit  one  square  foot  at  the  maximum  practicable 
rate.  Curiously  enough  there  is  a  wide  divergence  of 
opinion  among  authorities  as  to  the  quantity  of  current 
which  may  be  advantageously  employed.  V.  Hiibl 
gives  the  maximum  as  36  amperes  with  an  agitated  solu- 
tion. Sprague  and  Watt  place  the  maximum  at  37 
amperes,  while  other  writers  claim  that  from  75  to  100 
amperes  may  be  employed.  It  is  probable,  however, 
that  the  latter  estimates  are  made  without  considerations 
of  economy.  It  would  no  doubt  be  possible  to  employ 
100  amperes,  but  at  a  tremendous  waste  of  power  in 
overcoming  the  resistance  due  to  polarization,  which 
increases  "  at  a  rate  approaching  that  of  the  square 
root  of  the  current. "  It  is  probable  that  50  amperes 
per  square  foot  cannot  be  exceeded,  if  consideration  be 
given  to  economical  working. 

Depositing  vats  vary  in  dimensions,  and  for  that 
reason  a  conducting  rod  which  would  be  of  ample 
capacity  in  one  case  would  be  too  small  in  another. 
Inasmuch  as  the  difference  in  the  cost  between  a  small 


96  ELECTROTYPING. 

rod  and  a  large  one  is  inconsiderable,  it  is  always  wise 
to  err  on  the  side  of  safety.  The  text-books  recom- 
mend a  cross-sectional  area  in  the  conductor  of  one 
square  inch  for  each  500  amperes,  and  in  practice,  rods 
of  this  size  have  been  found  to  be  of  ample  capacity. 
The  resistance  of  a  conductor  is  proportional  to  its 
length  as  well  as  to  its  cross-sectional  area,  and  this  rule 
applied  to  electrotyping  means  that  the  dynamo  should 
be  located  in  the  immediate  neighborhood  of  the  depos- 
iting vats.  For  the  purpose  of  conducting  the  current, 
the  cross  rods,  i.  e.,  the  rods  from  which  the  anodes  and 
molds  are  suspended,  do  not  usually  require  to  be  more 
than  one-fifth  the  size  of  the  main  conductors,  but  inas- 
much as  it  is  their  province  to  sustain  the  weight  of  the 
heavy  anodes  they  should  not  be  less  than  one-half  inch 
in  diameter. 

Less  trouble  will  be  found  in  making  good  connec- 
tions if  the  main  conducting  rods  are  rectangular  in 
shape,  as  in  that  case  the  cross  rods  which  rest  upon 
them  will  have  a  larger  area  of  contact  surface,  particu- 
larly if  the  ends  are  slightly  flattened.  If  the  main 
conductors  are  round,  the  ends  of  the  cross  rods  should 
be  not  only  flattened  but  curved  to  fit  over  the  larger 
rods,  and  thus  insure  a  good  contact.  The  anodes  are 
usually  suspended  in  the  solution  by  two  copper  hooks, 
which  should  be  large  enough  to  transmit  the  current 
without  becoming  sensibly  heated — say  three-eighths  of 
an  inch  in  diameter.  These  hooks,  like  the  cross  rods, 
should  be  flattened  and  curved  in  order  to  insure  ample 
contact    surface.      Undoubtedly   the    best    method    of 


ELECTROTYPING.  97 

suspending  the  anodes  is  to  drill  and  tap  holes  in  the 
ends  and  screw  the  suspending  hooks  into  them.  This 
makes  a  perfect  connection,  and  will  remain  as  long  as 
the  anodes  last. 

It  has  been  frequently  noted  that  electrotypers  do 
not  always  appreciate  the  importance  of  making  good 
connections.  It  is  of  no  avail  to  provide  large  conduct- 
ing rods  and  cross  rods  if  the  conducting  capacity  of 
the  rods  is  to  be  choked  off  at  the  point  of  connection, 
which  is  what  occurs  when  one  round  rod  is  laid  across 
another  round  rod.  It  should  be  plainly  obvious  that 
unless  one  or  both  of  the  rods  are  flattened  where  they 
come  in  contact,  the  area  of  the  contact  will  be  extremely 
limited  compared  with  the  area  of  the  conductors  on 
both  sides  of  the  contact.  It  is  hardly  necessary  to  say 
that  all  contact  points  should  be  kept  clean  and  bright. 
A  neglected  rod  will  soon  become  corroded,  and  corro- 
sion increases  resistance  and  is  a  frequent  cause  of  heat. 

It  should  not  be  forgotten  that  the  solution  is  a  con- 
ductor of  the  current  in  the  same  sense  that  the  rods 
are,  and  should  be  considered  in  that  capacity  as  well 
as  a  dissolving  medium.  Pure  sulphate  of  copper  solu- 
tion is  an  extremely  poor  conductor.  The  addition  of 
sulphuric  acid  improves  its  conductivity,  but  under  the 
most  favorable  conditions  its  resistance  is  several  million 
times  greater  than  copper.  To  reduce  this  resistance 
to  a  point  where  the  solution  will  not  become  appreci- 
ably heated  by  the  passage  of  a  strong  current  it'  is 
necessary  to  provide  an  exceedingly  large  area  of  con- 
ducting fluid  and  to  suspend  the  anodes  and  cathodes 

7 


98  ELECTROTYPING. 

as  near  together  as  possible,  say  two  to  three  inches 
apart.  According  to  Joule's  law,  previously  quoted, 
the  development  of  the  heat  will  be  the  greater  the 
smaller  the  cross-section  of  the  conductor  and  its  con- 
ducting capacity  are,  and  the  larger  the  quantity  of 
current  which  passes  through  it.  If,  therefore,  it  is 
desired  to  employ  a  very  strong  current,  the  vats  must 
be  larger  in  proportion  to  the  size  of  the  anodes  than 
would  be  necessary  with  a  moderate  current.  It  is  safe 
to  say  that  the  cross-sectional  area  of  the  solution  should 
be  at  least  double  the  area  of  the  anodes. 


ELECTROTYPING.  99 


CHAPTER   XIV. 


DEPOSITING. 


WHEN  a  mold  has  been  metallized  by  the  dry 
graphite  method,  and  before  proceeding  to 
strike  it  (i.  e.,  precipitate  on  its  surface  a  preliminary 
coating  of  copper  to  render  it  more  conductive),  it  is 
essential  that  the  air  shall  be  expelled  from  its  surface 
by  thoroughly  wetting  it,  otherwise  the  mold  when  first 
immersed  in  the  bath  will  be  apt  to  repel  the  liquid,  and 
the  film  of  air  retained  on  its  surface  will  partially  insu- 
late the  mold  and  cause  holes  in  the  shell.  Wetting 
may  be  accomplished  by  pouring  over  the  mold  a  small 
quantity  of  alcohol  or  wood  spirits.  A  more  economical 
method  consists  in  placing  the  mold  face  up  on  a  shelf 
in  a  tank  partially  filled  with  water  in  such  a  manner 
that  it  will  rest  an  inch  or  two  under  the  surface,  and 
then  by  means  of  a  rotary  pump  and  a  rose  nozzle 
direct  a  stream  of  water  upon  it.  In  some  foundries 
graphite  is  mixed  with  the  water,  in  which  case  the 
apparatus  becomes  an  auxiliary  blackleader  and  aids 
in  the  metallization  of  the  mold. 

After  wetting  and  striking  the  mold  it  should  be 
immediately  suspended  in  the  bath  from  one  of  the  rods 
connected  with  the  negative  pole  of  the  dynamo  or  bat- 


100  ELECTROTYPING. 

tery.  It  will  be  recalled  that  the  current  enters  the 
bath  through  the  positive  electrode  and  leaves  it 
through  the  negative.  It  is  obvious,  therefore,  that 
were  the  mold  suspended  from  the  positive  rod  no 
action  would  result. 

The  anodes  are  solid  plates  of  rolled  copper  of  any 
convenient  thickness,  but  they  should  have  as  nearly  as 
possible  the  same  area  of  exposure  as  the  cathodes.  If 
the  anode  be  much  smaller  than  the  cathode  the  deposit 
will  be  brittle  and  the  solution  become  impoverished. 
If  the  anode  should  be  much  larger  than  the  cathodes 
copper  will  be  dissolved  faster  than  it  is  deposited, 
increasing  the  density  of  the  solution  and  resulting  in 
streaks  on  the  back  of  the  electrotype  and  the  forma- 
tion of  uneven  deposits. 

Holes  in  the  shell  are  usually  due  to  defective  black- 
leading  or  failure  to  expel  the  air  from  the  mold  by 
thorough  wetting.  In  some  instances,  however,  they 
are  caused  by  hydrogen  bubbles.  The  remedy  for  the 
latter  evil  is  to  decrease  the  current  strength  or  pass  a 
camel' s-hair  brush  lightly  over  the  mold  several  times 
during  the  time  it  is  in  the  bath,  or,  better  yet,  agitate 
the  solution. 

The  mold  should  be  examined  after  it  has  been  in 
the  bath  a  few  minutes,  and  if  any  dark  spots  are 
observed  it  should  be  at  once  removed  and  a  solution 
of  graphite  and  water,  or,  better  yet,  graphite  and  alco- 
hol, should  be  thoroughly  rubbed  into  the  defective 
spots.  The  mold  should  then  be  rinsed  under  a  strong 
head   of   water   applied   through   a   spray   nozzle   and 


ELECTROTYPING.  101 

returned  to  the  bath.  On  no  account  should  the  mold 
be  allowed  to  dry  while  out  of  the  bath. 

The  anodes  should,  of  course,  be  suspended  from 
the  positive  pole  of  the  dynamo,  and  it  is  evident  that 
only  one  anode  need  be  provided  for  each  pair  of 
cathodes,  for,  to  maintain  an  equal  area  of  exposure, 
a  mold  should  be  placed  on  each  side  of  the  anode. 

If  the  baths  are  arranged  in  series,  which  is  the  most 
economical  method  of  working,  the  total  number  of 
molds  should  be  divided  as  evenly  as  possible  between 
the  vats  to  insure  an  equal  rate  of  deposition. 

The  copper  sulphate  solution  requires  little  attention 
as  a  rule,  because  the  proportions  of  its  ingredients  may 
be  quite  widely  varied  without  materially  affecting  the 
quality  of  the  deposited  copper,  and,  on  the  other  hand, 
the  current  strength  may  also  be  varied  and  the  quality 
of  the  production  still  remain  satisfactory;  but,  notwith- 
standing these  facts,  it  is  possible  to  make  the  solution 
too  rich  or  too  poor  in  metal,  or  too  weak  or  too  strong 
with  acid,  and  the  current  density  may  be  too  great  to 
work  in  harmony  with  the  solution.  Very  often  a 
defective  shell  may  result  from  one  of  two  or  three 
causes.  It  is,  therefore,  sometimes  necessary  to  experi- 
ment a  little  in  order  to  determine  the  exact  cause  of 
the  trouble.  For  instance,  a  sandy,  pulverulent  deposit 
may  be  caused  by  an  excess  of  current,  or  it  may  be 
caused  by  an  excess  of  metal  in  the  solution,  or  both. 
A  brittle  deposit  will  be  caused  by  a  weak  current,  or  a 
solution  poor  in  metal,  or  both.  But  if  the  electro- 
typer  be  provided  with  an  accurate  voltmeter  it  is  a 


102 


ELECTROTYPING. 


comparatively  easy  matter  to  locate  the  cause  of  the 
trouble,  for  if  the  instrument  indicates  a  current  of  suit- 
able tension  for  a  properly  proportioned  solution,  it  may 
be  assumed  that  the  cause  of  the  defective  deposits  will 
be  found  in  the  bath  and  may  be  removed  by  enriching 
or  diluting  the  solution  as  may  be  indicated  by  the  char- 
acter of  the  deposited  copper. 

Under  ordinary  conditions  of  current  and  solution, 
the  molds  should  be  separated  from  the  anodes  by  a 
distance  of  about  two  inches;  but  if  it  is  found  that  the 
deposit  is  very  dark  in  color  or  granulated  in  texture, 
this  distance  may  be  increased,  thereby  increasing  the 
resistance  of  the  solution,  which  is  equivalent  in  its 
effect  to  cutting  down  the  current  strength. 

After  working  a  few  hours  the  anodes  become  more 
or  less  coated  with  slime,  consisting  of  impurities  and 
small  quantities  of  foreign  metals,  which  are  always 
present  to  a  greater  or  less  extent  in  rolled  copper.  To 
remove  the  slime,  which  has  the  effect  of  partially  insu- 
lating the  anodes,  they  should  be  removed  from  the 
bath  once  every  day  and  thoroughly  scrubbed  and 
rinsed  with  clean  water. 

When  molds  are  removed  from  the  bath  the  anodes 
should  always  be  disconnected  from  the  dynamo,  as 
otherwise  copper  would  be  dissolved  into  the  solution, 
thereby  unduly  increasing  its  density. 

The  length  of  time  required  to  deposit  a  shell  of 
given  thickness  depends  on  the  current  -  strength  em- 
ployed and  the  condition  of  the  solution  and  connec- 
tions.    According  to  Gore,  a  current  density  of  17.94 


ELECTROTYPING.  103 

amperes  per  square  foot  will  deposit  .001  inch  of  copper 
per  hour;  35.88  amperes  will  deposit  .002  per  hour,  and 
so  on.  Having  ascertained  the  current-strength  avail- 
able there  would  be  no  difficulty  in  calculating  the  time 
necessary  to  obtain  a  deposit  of  any  required  thickness 
provided  it  were  certain  that  no  variation  in  the  current 
would  occur,  and  that  the  connections  would  remain 
clean  and  in  perfect  contact,  for  having  once  ascertained 
the  time  required  to  deposit  a  satisfactory  shell,  it  would 
be  safe  to  assume  that  the  same  results  would  be  obtained 
thereafter;  but  carelessness  in  the  preparation  of  molds, 
as  well  as  dirty  rods  or  connections,  sometimes  delays 
the  action  of  the  current,  and  the  electrotyper,  after  the 
calculated  time,  usually  separates  one  corner  of  the  shell 
from  the  mold  with  a  sharp-pointed  tool,  and  tests  its 
thickness  by  bending  it  back  and  forth.  This  would 
seem  to  be  a  "  rule-of-thumb ' '  method  of  working,  but 
constant  practice  makes  the  workman  so  expert  that  he 
seldom  makes  a  mistake.  In  establishments  where  the 
volume  of  work  is  large,  it  is  customary  to  provide  time 
tags  which  may  be  attached  by  clothes  pins  or  other 
devices  to  the  molds  or  cross-rods.  When  the  mold  is 
suspended  in  the  bath,  a  tag  is  attached  on  which  is 
written  the  hour  it  is  due  to  come  out.  In  this  way  the 
electrotyper  is  enabled  to  keep  tab  on  his  work  and 
avoids  waste  of  time  in  testing  work  which  has  been 
insufficiently  exposed;  for  while  it  sometimes  happens 
that  a  longer  time  is  required  to  deposit  a  shell  than 
would  be  indicated  by  the  voltmeter  or  ammeter,  it  never 
takes  less  than  the  time  so  indicated. 


104  ELECTROTYPING. 

The  electrotypers'  sink  should  be  of  ample  dimensions 
and  should  be  provided  with  an  unlimited  supply  of  hot 
and  cold  water.  The  cold  water  faucet  should  be  a  hose 
bib,  to  which  should  be  attached  a  short  piece  of  hose 
terminating  in  an  adjustable  nozzle,  to  provide  either  a 
spray  or  a  strong  stream  of  water  as  circumstances  may 
demand.  The  hot  water  should  be  kept  in  a  tank  at 
one  end  of  the  sink,  from  which  it  may  be  dipped  as 
needed.  One  end  of  the  sink  should  be  provided  with 
a  hinged  apron  to  protect  the  operator  and  the  floor 
from  the  spray  when  using  a  strong  head  of  water  such 
as  is  necessary  in  washing  out  molds. 


ELECTROTYPING. 


105 


CHAPTER  XV. 


CASTING, 


ELECTROTYPERS'  furnaces  were  formerly  con- 
structed of  brick  with  an  iron  kettle  and  face 
plate.  These  furnaces  are,  however,  seldom  seen  now, 
the  modern  furnace  (Fig.  15)  being  constructed  of  iron, 
lined  with  fire  brick.  It  occupies  less  room  than  the  old 
style  furnace,  is  set  up  several  inches  from  the  floor  to 
provide  an  air  space  underneath  and  thus  minimize  the 


Fig.  15.— ELECTROTYPERS'  Furnace. 


106  ELECTROTYPING. 

danger  from  fire,  and  it  may  be  moved  from  one  place 
to  another  when  desired  without  tearing  it  to  pieces. 
The  kettle  is  square  or  oblong  in  shape,  for  convenience 
in  floating  the  backing  pans,  and  is  about  six  inches 


Fig.  i6.— Leveling  Stand. 

deep,  A  wide  flange  or  shelf  extends  around  the  top 
of  the  furnace  to  provide  a  convenient  resting  place  for 
the  backing  pans  and  body  molds.  The  floor  vmder 
the  furnace  and  for  some  distance  in  every  direction 
should  be  covered  with  heavy  sheet  iron,  about  No.  i6 
gauge. 

The  leveling  stand  (Fig,  i6),  upon  which  the  back- 
ing pans  rest  while  the  cast  is  poured,  is  a  light  but 
substantial  framework  of  iron,  whose  upper  rails  are 
provided  with  T-screws  which  may  be  so  adjusted  as  to 


ELECTROTYPING. 


107 


keep  the  pan  always  in  a  level  position  and  thus  insure 
a  cast  of  uniform  thickness. 

The  backing  pan  (Fig.  17)  is  a  plate  of  iron  or  steel, 
planed  perfectly  true  and  surrounded  with  a  raised  edge 
whose  height  determines  the  thickness  of  the  cast.  The 
pan  is  provided  with  handles  to  facilitate  handling. 
Where  the  pans  are  large  it  is  customary  to  handle 
them  by  means  of  a  crane  with  an  arm  of  sufficient 
length  to  swing  them  from  the  furnace  to  the  leveling 


Fig.  17.— Backing  Pan. 

stand.  Backing  pans  should  always  be  kept  perfectly 
clean,  and  to  that  end  should  be  scoured  after  each  cast. 
Unless  they  receive  proper  attention  in  this  respect  they 
will  soon  become  rusted  and  totally  unfit  for  the  purpose 
for  which  they  are  designed ;  for  to  assure  a  perfect  cast 
it  is  essential  that  the  shell  shall  lie  perfectly  flat  upon  a 
smooth  and  level  surface. 

Backing  metal  is  composed  of  lead,  tin  and  anti- 
mony. A  popular  mixture  is  lead  90  pounds,  tin  5 
pounds,  antimony  5  pounds.  However,  the  proportions 
of  tin  and  antimony  are  sometimes  varied.  Some  elec- 
trotypers  prefer  4  pounds  of  tin  and  6  of  antimony, 
and  others  6  pounds  of  tin  and  4  of  antimony.     The 


108  ELECTROTYPING. 

requirements  are  that  the  metal  shall  be  soft  enough  to 
straighten  easily  under  the  hammer  and  punch,  yet  not 
so  soft  as  to  crush  down  on  the  press,  and  it  must 
contain  tin  in  sufficient  quantity  to  insure  perfect  adhe- 
sion of  the  metal  to  the  copper  shell. 

Having  deposited  a  shell  of  satisfactory  weight,  the 
mold  is  removed  from  the  bath  and  placed  in  the  sink 
in  a  slanting  position.  After  cutting  the  connections,  a 
small  quantity  of  hot  water  is  poured  over  the  mold, 
beginning  at  the  upper  end  and  allowing  it  to  flow 
down  over  every  portion  of  its  surface.  The  heat 
softens  the  wax  and  releases  the  shell,  which  should  be 
carefully  handled  to  prevent  buckling  or  bending. 
After  rinsing  the  shell  in  cold  water  it  should  be  washed 
with  hot  potash  to  remove  the  film  of  wax  which  will 
still  adhere  to  the  copper.  The  shell  may  be  placed  on 
a  slanting  board  over  the  lye  kettle  and  scrubbed  lightly 
with  a  soft  brush,  and  then  rinsed  with  potash  and  after- 
ward with  clean  water.  Unless  the  shells  are  to  be 
immediately  backed  up  with  metal,  they  should  be 
placed  in  a  shallow,  lead-lined  box  partially  filled  with 
water  slightly  acidulated  with  sulphuric  acid.  If  the 
shells  are  permitted  to  become  dry  they  will  tarnish  and 
will  not  readily  amalgamate  with  the  backing  metal. 

In  order  to  effectually  unite  the  backing  metal  to 
the  shells  it  is  essential  that  the  back  of  the  shell  shall 
be  perfectly  clean,  and  that  it  shall  be  first  covered  with 
a  coating  of  solder  or  with  tin  foil,  which  becomes 
solder  when  mixed  with  the  lead  in  the  backing  metal. 
Tin  foil  may  be  purchased  in  rolls  of  any  desired  width 


ELECTROTYPING.  109 

and  thickness.  A  convenient  size  is  five  or  six  inches 
in  width  and  about  .002  inch  in  thickness. 

To  thoroughly  clean  the  shell  it  should  be  brushed 
over  with  a  solution  of  chloride  of  zinc,  which  may  be 
prepared  by  dissolving  scraps  of  sheet  zinc  in  muriatic 
acid  to  saturation  and  adding  twenty-five  per  cent  pure 
water.  The  zinc  should  be  dissolved  in  a  wide-mouthed 
bottle  in  the  open  air,  as  the  fumes  given  oflf  are  disa- 
greeable and  poisonous.  The  zinc  solution  may  be 
applied  with  a  bristle  brush,  and  the  operation  may 
preferably  be  performed  on  a  glass-topped  table  or  on 
a  sheet  of  heavy  plate  glass  placed  on  the  workbench. 
Glass  is  preferred  because  it  is  not  affected  by  acid  and 
may  be  easily  kept  clean. 

After  cleaning  with  the  tinning  solution  the  shell  is 
covered  with  tin  foil  and  placed  face  down  in  the  back- 
ing pan,  which  has  been  previously  heated  by  floating 
it  in  the  molten  metal,  whose  temperature  should  be 
sufficiently  high  to  scorch  a  piece  of  white  paper  with- 
out burning  it.  The  tin  will  almost  immediately  melt 
and  cover  the  shell  with  a  thin  coating.  If  preferred, 
the  shell  may  be  placed  on  an  iron  plate  heated  by  gas 
instead  of  in  the  backing  pan,  the  object  being  to  melt 
the  tin  foil  on  the  shell.  After  the  tin  is  melted  the 
backing  pan  should  be  immediately  transferred  to  the 
leveling  stand  and  the  shells  covered  with  molten  metal, 
pouring  it  on  slowly  from  a  small  ladle  and  holding  the 
shell  down  with  a  stick  or  any  convenient  instrument  if 
it  shows  any  inclination  to  rise  to  the  surface  of  the 
metal. 


no  ELECTROTYPING. 

To  expedite  cooling  of  the  cast  a  small  blower  may 
be  placed  on  the  floor  under  the  leveling  stand  in  such 
a  manner  that  a  stream  of  air  may  be  directed  against 
the  bottom  of  the  pans. 

A  device  which  is  sometimes  employed  in  connection 
with  the  backing-up  process  and  which  is  claimed  to 


Fig.  19. 


accomplish  a  material  saving  of  time  and  labor  is  illus- 
trated in  Fig.  19.  The  description  is  taken  from  the 
circular  of  the  manufacturer. 

The  apparatus  is  designed  to  flatten  the  plates  by 
pressure  after  the  metal  has  been  poured  and  before  it 
has  set  and  hardened.     The  process  differs  but  little 


ELECTROTYPING.  •         111 

from  that  hitherto  employed,  the  new  feature  being 
the  application  of  pressure,  whereby  much  of  the  ham- 
mering and  finishing  is  obviated. 

The  press  has  been  so  designed  as  to  make  it  thor- 
oughly efficient  and  convenient,  many  suggestions  from 
experienced  electrotypers  being  embodied  in  its  con- 
struction. Its  operation  is  very  simple,  presenting  no 
difficulties. 

When  the  pan  is  lifted  out  of  the  metal  pot  the 
metal  that  adheres  to  the  bottom  of  the  pan  is  scraped 
off  by  a  steel  scraper  attached  to  the  front  end  of  the 
press.  On  the  inner  sides  of  the  frame  of  the  press 
are  rollers,  seven  on  each  side,  upon  which  the  pans 
move  easily  and  quickly.  The  pan  is  set  on  the  rollers 
on  the  front  of  the  press  and  the  shell  backea  as  usual. 
Air  is  blown  on  the  bottom  of  the  pan  from  a  pipe 
underneath,  and  on  the  metal  from  a  pipe  above,  the 
object  being  to  cool  the  cast  evenly  as  well  as  quickly. 
When  the  metal  has  commenced  to  set,  a  sheet  of  thick 
asbestos,  covered  with  powdered  chalk  or  blacklead,  is 
laid  on  top  of  it  and  the  pan  rolled  under  the  platen. 
The  blast  is  then  turned  on  the  bottom  of  the  pan 
under  the  platen.  The  rollers  under  the  platen  are  on 
springs,  and  depressed  by  the  pressure  on  the  pan  until 
the  pan  rests  on  supports  underneath.  The  asbestos 
and  the  rollers  being  elastic,  the  pressure  is  gradual  and 
easy.  The  pan  remains  under  pressure  till  the  next 
one  is  ready,  and  is  then  pushed  out  to  the  back  of  the 
press  and  taken  off.  The  blast  pipes  underneath  are 
supplied  with   the  press  and  provided  with  dampers. 


112 


ELECTROTYPING. 


They  are  so  arranged  that  connection  can  be  made  with 

the  pipe  from  the  blower  on  either  side  of  the  press. 

Electrotypes  are  usually  mounted  on  wooden  blocks 

to  make  them  "type  high,"  but  for  certain  purposes  it 


Fig.  20. 

is  desirable  to  mount  them  on  metal  bases,  as,  for 
instance,  half-tone  cuts  and  matter  which  is  to  be 
stereotyped,  such  as  advertising  cuts  for  daily  news- 
papers. For  the  latter  purpose  electrotypes  are  made 
in  standard  widths,  i.  e. ,  single,  double  or  triple  column. 
The  electrotype,  after  it  has  been  backed  up  and 
straightened,  may  be  tacked  or  soldered  to  metal  bases 
which  have  been  previously  trimmed  and  shaved  to  the 
proper  dimensions,  but  better  results  are  obtained  both 
in  appearance  and  security  by  casting  the  base  directly 


ELECTROTYPING. 


113 


on  to  the  plate  by  placing  the  electrotype  face  down  in 
an  iron  mold  and  pouring  molten  metal  on  the  back. 
The  cover  of  the  mold  is  provided  with  corrugations 
which  form  depressions  in  the  metal,  thus  effecting  a 
saving  in  material  and  at  the  same  time  producing  a 
cast  both  light  and  strong  and  more  easily  handled 
than  a  solid  metal  cast. 

Figs.  20  and  21  illustrate  respectively  a  body  mold 
and  a  section  of  a  cast  made  therein.  The  bottom 
plate  of  the  mold  on  which  the  electrotype  rests  is  not 
shown. 


Before  making  a  cast  all  parts  of  the  mold  are 
floated  in  the  metal  pot  until  they  are  of  uniform  tem- 
perature with  the  metal.  With  a  pair  of  pincers  or 
tongs  the  bottom  plate  is  then  withdrawn  from  the  metal 
and  placed  on  two  supporting  blocks,  one  under  either 
end,  one  of  which  is  slightly  higher  than  the  other,  so 
that  the  plate  will  have  a  pitch  of  about  one-half  inch. 
The  frame  of  the  mold  is  then  laid  on  the  bottom  plate, 
the  electrotype  placed  inside,  the  cover  adjusted  and  the 
8 


114  ELECTROTYPING. 

different  parts  clamped  together  with  two  iron  haind 
clamps.  The  cover  is  somewhat  shorter  than  the  frame, 
which  leaves  an  opening  at  the  upper  end  to  receive  the 
metal.  The  temperature  of  the  mold  is  sufficient  to 
soften  the  backing  of  the  electrotype,  so  that  the  new 
metal,  which  is  poured  slowly  and  cautiously,  readily 
amalgamates  with  it.  Having  filled  the  mold,  the  cast 
may  be  cooled  by  swabbing  the  mold  with  cold  water. 
As  the  metal  cools  it  shrinks  and  more  metal  must  be 
continually  added  until  the  cast  is  set. 

Electrotype  body  molds  are  made  in  several  standard 
sizes,  from  6  to  41  picas  in  width  and  about  14  inches 
long.  Electrotypes  wider  than  41  picas  are  cast  in 
adjustable  molds,  an  illustration  of  which  is  shown  in 
Fig.  22.  In  such  a  mold  electrotypes  from  one-half  to 
four  columns  in  width  may  be  cast  solid  or  cored. 
Eight  cores  of  different  sizes  are  usually  provided, 
suitable  for  different  kinds  of  work. 

In  some  foundries  the  mold  is  cooled  after  the  cast 
has  been  poured  by  partially  immersing  it  in  a  tank  of 
water.  When  employing  this  method  it  is  important 
that  the  cooling  shall  be  effected  gradually,  otherwise 
uneven  shrinkage  would  result  and  the  electrotype  be 
injured  or  destroyed.  A  convenient  means  of  handling 
the  molds  is  by  means  of  a  small  derrick  which  may  be 
locked  in  any  desired  position  and  thus  permit  the  grad- 
ual immersion  of  the  mold  in  the  water. 

After  the  shell  has  been  backed  up,  the  cast  is  taken 
to  the  scrubbing  trough  and  thoroughly  cleaned  with 
kerosene  and   powdered  pumice  stone  applied  with  a 


ELECTROTYPING. 


115 


moderately  stiff  brush,  and  finally  polished  and  dried 
with  soft  sawdust.  Great  care  should  be  observed  in 
cleaning  half-tones,  as  a  slight  scratch  is  sufficient  to 
ruin  them. 

The  backing  pan  will  usually  accommodate  several 
shells,   and  after  they  have  been  cast  and  cleaned  the 


next  operation  is  to  saw  the  different  jobs  apart  that 
that  they  may  be  separately  straightened  and  finished. 
For  this  purpose  an  iron  saw  table  is  employed,  of  which 
Fig.  23  is  an  illustration.  The  mandrel  is  driven  by  a 
countershaft  and  pulleys  which  are  furnished  with  the 


116 


ELECTROTYPING. 


machine.  The  rear  end  of  the  table  is  hinged  to  the 
frame  of  the  machine;  the  front  rests  on  the  end  of 
a  screw,  terminating  in  a  hand  wheel,  by  means  of 
which  the  top  may  be  adjusted  to  any  desired  height  for 
sawing  mortices,  etc.  An  adjustable  side  gauge  and  a 
sliding  end  gauge  are  necessary  features  if  the  saw  is  to 


Fig.  23. 


ELECTROTYPING.  117 

be  used  for  general  work,  and  a  glass  saw  guard  for 
protecting  the  eyes  of  the  operator  from  flying  chips 
and  sawdust  is  also  essential. 

Saw  blades  for  cutting  electrotype  metal  should  have 
about  the  same  temper  as  for  sawing  wood,  and  should 
not  be  of  greater  diameter  than  the  nature  of  the  work 
demands.  A  large  saw  is  liable  to  wind  and  warp,  while, 
on  the  other  hand,  if  it  projects  but  slightly  through 
the  work  this  tendency  will  be  minimized.  The  diam- 
eter of  the  saw  must  depend,  of  course,  upon  the  dis- 
tance between  the  saw  mandrel  and  the  table  top.  For 
instance,  if  the  saw  mandrel  is  three  inches  below  the 
top  of  the  table,  a  nine-inch  saw  would  be  required  to 
give  sufficient  cutting  surface  above  the  table  and  allow 
for  a  reasonable  amount  of  wear.  In  most  machines, 
however,  the  mandrel  is  located  within  two  and  one-half 
inches  from  the  top,  or  even  less,  thus  permitting  the 
use  of  smaller  blades.  For  general  use  a  cross-cut  saw, 
eight  inches  in  diameter.  No.  i8  or  19  gauge,  and  with 
about  five  points  to  the  inch,  is  found  most  practical  and 
convenient.  Such  a  saw  should  be  driven  about  4,000 
revolutions  a  minute. 

To  cut  freely  without  sticking  or  filling  up,  saws 
should  be  kept  sharp,  round,  evenly  set,  and  the  teeth 
should  be  filed  all  with  the  same  angle  and  without 
hook.  To  keep  the  saw  round,  it  should  be  jointed 
occasionally  by  elevating  the  table  top  until  only  the 
longer  teeth  of  the  saw  project  through  the  slot  in  the 
top,  when  they  may  be  ground  down  with  a  piece  of 
emery  stone  to  uniform  length.     If  the  saw  mandrel  fits 


1 18  ELECTROTYPING. 

perfectly  the  hole  in  the  saw  and  no  more  filing  is  done 
than  is  necessary  to  bring  the  teeth  to  a  point,  a  perfect 
circle  will  by  this  method  be  obtained. 

The  saw  may  be  set  by  laying  it  on  a  block  of  hare- 
wood  and  striking  every  alternate  tooth  with  a  hammer 
or  punch,  and  then  turning  it  over  and  repeating  the 
operation  with  the  remaining  teeth.  It  requires  consid- 
erable skill,  however,  to  set  a  saw  evenly  in  this  way, 
and  it  is  preferable,  particularly  for  the  novice,  to  use  a 
carpenter's  saw  set  which  may  be  purchased  at  any 
hardware  store. 

To  file  a  saw  properly  it  should  be  clamped  between 
two  round  blocks,  about  one  inch  thick  and  one  inch 
less  in  diameter  than  the  saw.  The  blocks  may  be 
clamped  together  on  the  saw  by  placing  them  in  a  vise. 
The  saw  should  be  filed  straight  across  and  should  not 
hook  or  lean  forward  of  a  line  drawn  from  the  center  of 
the  saw  to  its  periphery. 


ELECTROTYPING.  119 


CHAPTER   XVI. 


FINISHING, 


THE  duties  of  the  electrotype  finisher  are  to  make 
the  face  of  the  electrotype  perfectly  flat  and  level, 
to  repair  defective  letters,  or  cut  them  out  and  replace 
them  with  type;  to  repair  defective  rules,  etc.,  and 
finally  to  bevel  the  edges  of  the  plates  if  they  are  to 
be  worked  on  patent  blocks,  or  to  mount  them  upon 
wooden  or  metal  bases. 

The  tools  required  to  properly  straighten  an  electro- 
type are  a  light  hammer,  with  one  round  face,  Fig.  24; 
a  set  of  punches,  Fig.  25;  a  pair  of  calipers.  Fig.  26, 
and  a  rubber,   Fig.    27. 

The  first  operation  is  to  beat  down  the  edges  of  the 
bearers  surrounding  the  page  or  engraving  with  the 
hammer,  after  which  the  plate  is  laid  face  down  on  a 
smooth,  steel-faced  finishing  block,  and  planed  down 
with  a  block  of  wood  and  hammer  to  make  it  lie  flat 
and  solid.  If  any  bad  sinks  are  observed  in  the  electro- 
type their  exact  location  is  marked  on  the  back  of  the 
plate  by  means  of  the  calipers.  The  plate  is  then  again 
laid  on  its  face  on  the  finishing  block,  and  with  a  suit- 
able punch  the  marked  spot  is  driven  down  until  it  is 
flush  with  the  surrounding  matter.  After  the  plate  has 
been  rough-finished  and  straightened  it  is  taken  to  the 
rougher.  Fig.  28,  and  a  cut  taken  off  the  back,  which 
reduces  it  to  an  approximately  uniform  thickness. 


120 


ELECTROTYPING. 


As  its  name  implies,  the  rougher  was  designed  to 
take  the  first  or  rough  cut  ofT  from  the  electrotype  cast. 
Its  chief  utility  consists  in  the  fact  that  a  large  quan- 
tity of  "metal  may  be  removed  at  one  operation.  The 
electrotype  rests  face  down  upon  a  traveling  bed,  and 


Fig.  24. 


Fig.  25. 


is  held  down  during  the  operation  of  planing  by  two 
spring  rolls  located  one  on  either  side  of  the  track  of  a 
reciprocating  cutter.  The  cutter  is  secured  in  a  tool 
post  which  is  arranged  to  slide  on  an  arm  extending 
over  the  bed  and  at  right  angles  thereto.  The  cutter  is 
actuated  by  a  pitman,  one  end  of  which  is  connected 
with  a  stud  on  the  cutter  head  and  the  other  with  a  stud 


ELECTROTYPING. 


121 


on  the  drive  pulley.  The  bed  is  operated  in  one  direc- 
tion by  a  worm,  which  is  driven  by  a  belt  from  a  pulley 
on  the  drive  shaft,  and  is  reversed  by  hand. 


Fig.  26. 


While  the  machine  was  originally  intended  for  rough 
work,  yet  if  carefully  constructed  it  can  be  made  to  per- 
form its  duty  so  accurately  that  no  further  planing  or 
shaving  is  necessary,  and  in  many  foundries  it  takes  the 
place  of  the  shaving  machine. 

An  improved  type  of  rougher  has  an  adjustable 
shaving  knife  located  just  back  of  the  reciprocating 
cutter,  which  frees  the  plate  from  the  metal  chips  which 


Fig.  27. 


become  imbedded  in  the  plate  by  passing  under  the 
spring  roller,  and  which  would  otherwise  have  to  be 
removed  with  a  file  or  scraper.  The  shaver  knife  also 
removes  the  tool  marks  left  by  the  rougher,  and  gives 
the  plate  a  finished  appearance. 


122 


ELECTROTYPING. 


After  the  electrotype  has  been  roughed  it  is  taken 
back  to  the  finishing  block  and  carefully  examined. 
Every  minor  defect  is  then  remedied  and  necessary 
corrections  made. 

To  more  readily  detect  the  low  spots  in  the  plate, 
the  face  of  the  electrotype  is  lightly  rubbed  over  with  a 
rubber  ink  eraser,  mounted  on  a  block  of  wood,  or  with 
a  piece  of  fine  emery  paper  stretched  over  a  block. 
Those  portions  of  the  electrotype  which  do  not  receive 
a  polish  from  this  treatment  are  obviously  low,  and  after 
locating  them  on  the  back  of  the  plate  with  the  aid  of 


Fig.  28. 


ELECTROTYPING.  128 

the  calipers,  they  are  hammered  or  punched  up  to  a 
uniform  level.  After  each  operation  of  hammering  or 
punching,  the  electrotype  is  planed  down  and  straight- 
ened, and  again  tested  with  the  rubber,  and  these  treat- 
ments are  repeated  until  all  the  dark  spots  have  been 
brightened. 

While  the  process  of  straightening  an  electrotype  as 
thus  described  is  very  simple,  it  really  calls  for  a  high 
degree  of  mechanical  skill,  which  can  be  acquired  only 
by  long  practice. 

The  electrotype  having  been  straightened  and  re- 
paired, it  is  taken  to  the  shaving  machine  for  a  final  cut, 
which  should  reduce  its  thickness,  if  a  book  plate,  to 
exactly  ii  points  (small  pica),  this  thickness  having  been 
adopted  by  the  electrotypers'  associations  of  America  as 
a  national  standard  for  bookwork.  If  the  plate  is  to  be 
mounted  on  a  wooden  base  it  may  be  shaved  somewhat 
thinner. 

Shaving  machines  are  of  various  patterns  and  sizes, 
some  operated  by  steam  power  and  some  by  hand.  The 
hand  shaver  consists  of  an  iron  table  planed  perfectly 
true  upon  its  upper  surface,  and  provided  with  a  stop  at 
one  end  to  hold  the  plate  in  position.  The  side  edges 
of  the  table  are  planed  true,  both  top  and  bottom,  and 
serve  as  guides  for  a  sliding  head  to  which  the  knife  is 
bolted.  Secured  to  the  rear  of  the  head  and  traversing 
the  entire  length  of  the  machine  are  steel  racks,  one  on 
either  side,  which  are  engaged  by  two  pinions  located 
on  a  shaft  which  is  at  right  angles  with  the  racks.  To 
one  end  of  the  shaft  a  cast-iron  spider  is  keyed,  and  to 
the  spider  long  wooden  spokes  are  bolted,  which  afford 
the  means  of  operating  the  head.    The  head  is  provided 


124 


ELECTROTYPING. 


with  brass  gibs,  and  the  wear  on  the  gibs  may  be  taken 
up  by  means  of  set  screws. 

In  large  establishments  shaving  machines  are  usually 
driven  by  steam  power.  There  are  various  devices  for 
applying   the   power,    one    of  which   is   illustrated   in 


Fig.  29, 


Fig.  29.  The  shaft  and  pinions  acting  on  the  racks 
are  the  same  as  in  the  hand  machine.  A  large  gear 
wheel  is  substituted  for  the  spoke  wheel  on  the  main 
shaft  and  is  driven  by  a  pinion  to  whose  shaft  power 
is  communicated  through  intermediate  gearing  by  means 
of  band  wheels  shown  at  the  left  of  the  machine. 


ELECTROTYPING. 


125 


Nearly  all  shaving  machines  are  provided  with  a 
spring  roller  located  in  front  of  and  attached  by  brack- 
ets to  the  head.  The  purpose  of  the  roller  is  to  press 
the  plate  flat  down  on  the  bed  of  the  machine  just 
before  the  knife  begins  its  cut.  A  plate  which  is  slightly 
uneven  or  warped  is  thus  secured  against  the  danger  of 
' '  go"gii^g> ' '  ^nd  the  necessity  for  planing  or  filing  a 
bevel  on  the  end  of  the  plate  is  also  obviated. 

Another  type  of  shaving  machine  has  a  bed  resting 
on  steel  wedges  which  are  made  adjustable  by  a  screw 


Fig.  30 


126  ELECTROTYPING. 

passing  through  the  front  of  the  machine  and  terminat- 
ing in  an  indexed  hand  wheel.  By  means  of  this  wheel 
the  bed  may  be  raised  or  lowered  to  any  desired  height 
within  the  range  of  the  machine. 

Fig.  30  illustrates  a  machine  which  is  of  compara- 
tively new  design  and  differs  in  many  respects  from 
other  makes.  The  following  description  is  given  by 
the  manufacturer:  "The  knife  remains  stationary,  the 
plate  to  be  shaved  being  placed  on  a  table  and  passed 
under  the  knife.  Power  is  applied  to  move  the  table 
in  one  direction  only,  the  power  being  thrown  on 
and  off  by  a  lever  handle,  not  shown,  convenient  to 
the  right  hand  of  the  operator.  The  backward  move- 
ment is  obtained  by  means  of  a  hand  wheel.  The  table 
is  extended  beyond  the  head  toward  the  front  of  the 
machine,  affording  increased  bearing  surface  and  equaliz- 
ing the  wear  over  all  parts  of  its  length ;  the  extended 
portion,  is  made  slightly  concave,  on  which  plates  may 
be  bent  so  that  they  shall  rest  properly  on  the  shaving 
table.  At  the  front  of  the  machine,  on  the  left  side,  is 
an  inverted  plane,  by  which  the  plates  may  be  beveled 
as  is  usual  to  prevent  the  too  abrupt  commencement  of 
the  shaving  operation. ' ' 


ELECTROTYPING. 


127 


CHAPTER   XVII. 


TRIMMING    AND    ROUTING. 


ALL  electrotype  plates,  whether  job  or  book  work, 
require  to  be  trimmed  on  sides  and  ends.  In 
the  case  of  wood-mounted  plates  the  trimming  is  done 
after  they  have  been  mounted  on  blocks,  when  plate 
and  block  may  be  finished  at  one  operation.  The  cir- 
cular saw  is  unsuited  for  such  work  because  of  its 
tendency  to  spring  away  from  the  job,  and  because  its 
cut  is  more  or  less  ragged  and  uneven. 


Fig.  31. 


Various  machines  have  been  designed  for  the  finish- 
ing of  electrotypes,  the  simplest  and  least  expensive  of 
which  is  the  shootboard,  Fig.  31,  which  consists  of  an 


128  ELECTROTYPING. 

iron  plate  with  a  gutter  or  chute  along  one  side  in  which 
a  plane,  furnished  with  an  adjustable  cutter  blade,  freely 
slides.  A  stop  extending  across  the  bed  at  right  angles 
with  the  gutter  serves  as  a  rest  for  the  electrotype  and 
also  as  a  guide  for  squaring  the  plate.     The  plane  is 


Fig.  32. 

provided  with  two  blades,  one  for  making  a  square  edge 
and  one  for  producing  a  beveled  edge  such  as  is  required 
on  book  plates. 

Fig.  32  illustrates  a  very  convenient  and  efficient 
trimming  machine,  specially  designed  for  finishing  type- 
high  or  ' '  body ' '  work.  A  rapidly  rotating  arbor  carry- 
ing a  cutter  head,  in  which  are  secured  two  or  more 


ELECTROTYPING.  *  129 

cutting  tools,  is  journaled  in  a  substantial  iron  frame. 
The  work  is  carried  past  the  cutters  on  a  reciprocating 
carriage  which  slides  on  ways  parallel  with  the  cutter 
head.  The  carriage  is  furnished  with  a  right-angled 
adjustable  gauge  against  which  the  work  rests,  which  is 
adjusted  by  a  finely  threaded  feed-screw,  admitting  of 
close  and  accurate  work.  The  trimmer  head  should 
travel  at  a  speed  of  about  3,500  revolutions  per  minute. 
To  prevent  the  work  from  being  drawn  into  the 
cutters  and  mangled  it  must  be  held  securely  on  the 
carriage.  Large  and  heavy  pieces  may  be  held  by  the 
fingers  without  danger,  but  the  very  small  pieces,  such 
as  one,  two  or  three  line  electrotypes,  should  be  held 
by  a  lineholder,   Fig.   33.     The  lineholder  is  an  oblong 


Fig.  33. 

block  of  iron  ten  or  twelve  inches  in  length,  two  inches 
in  width,  and  one  inch  high.  A  dove-tailed  groove, 
extending  the  full  length  of  the  side  face  of  the  block, 
admits  two  thin  serrated  clamps,  one  of  which  is  secured 
by  means  of  a  set  screw  at  any  desired  distance  from 
the  end  of  the  block,  and  the  other  is  pivoted  to  the 
end  of  a  lever  which  is  operated  by  a  handle  on  the 
top  of  the  block.  The  under  side  of  the  block  is 
recessed  to  receive  a  spiral  spring  which  is  attached  to 


130  ELECTROTYPING. 

the  lever  and  serves  to  hold  the  clamps  firmly  together 
upon  the  work.  In  operation  the  block  is  placed  upon 
the  carriage  of  the  trimmer,  the  clamp  jaws  separated 
by  means  of  the  handle  and  the  work  inserted  between 
them.  On  releasing  the  handle,  the  spring  acting  on 
the  lever  draws  the  clamps  together.  The  work  is  thus 
securely  held  and  may  be  trimmed  without  danger  to 
the  eyes  or  fingers  of  the  operator,  provided  the  line- 
holder  itself  be  held  firmly  against  the  side  gauge  of 
the  machine  during  the  operation  of  trimming.  It 
should  be  impressed  upon  the  workman  that  whether 
trimming  large  or  small  pieces  it  is  important  that  the 
carriage  be  kept  free  from  chips.  More  accidents  have 
been  caused  by  carelessness  in  this  regard  than  from  all 
other  causes  combined.  A  chip  or  a  small  piece  of 
metal  under  the  work  will  cause  it  to  chatter  or  rock 
when  it  encounters  the  cutters,  with  the  result  that  the 
workman  often  loses  control  of  it;  and  even  if  he 
is  not  injured  by  flying  fragments  his  work  will  be 
destroyed. 

Two  kinds  of  cutters  are  used  in  trimming  machines, 
one  for  trimming  metal  and  the  other  for  wood,  or  wood 
and  metal  combined,  such  as  job  or  book  plates  mounted 
on  cherry  or  mahogany  blocks.  The  cutters  should  be 
made  of  Stubs'  tool  steel,  hardened,  and  the  temper 
drawn  to  a  purple  color.  The  holes  in  the  cutter  head 
are  usually  made  round,  in  which  case  round  steel  of  a 
size  which  will  accurately  fit  the  holes  should  be  used 
for  tools.  The  cutting  ends  of  the  metal  cutters  must 
be  squared  for  at  least  a  half  inch  back  from  the  end  — 
that  is  to  say,  there  must  be  one  right-angled  corner  to 
do  the  cutting.     Fig.  34  is  a  side  and  end  view  of  a 


ELECTROTYPING. 


131 


metal  cutter,  and  Fig.  35  illustrates  a  wood  cutter  or 
"goose-bill." 

It  sometimes  becomes  necessary  to  deepen  the  relief 
in  an  electrotype  to  prevent  blacking  or  smutting  the 
paper  in  printing.     While  this  operation  may  be  per- 


FlG.  35. 


formed  with  a  mallet  and  chisel,  it  is  always  preferable 
to  employ  a  router.  Fig.  36.  In  this  machine  a  rapidly 
revolving  vertical  spindle  carries  on  its  lower  end  a 
chuck  in  which  may  be  secured  cutting  tools  of  various 
sizes  suited  to  the  nature  of  the  work  to  be  performed. 
The  box  in  which  the  spindle  turns  is  bolted  to  a  handle- 
bar, one  end  of  which  serves  as  a  handle  for  guiding  the 
tool  over  the  work,  while  the  other  end  is  pivoted  to 
another  handle-bar  which  is  again  pivoted  to  the  frame 
of  the  machine.  The  double  joints  thus  formed  permit 
the  tool  to  be  moved  freely  in  any  direction  over  the 
bed  of  the  machine.  The  second  handle-bar  is  sup- 
ported at  the  elbow  formed  by  pivoting  together  the 
two  bars,  by  a  steel  segment,  and  the  first  handle-bar 


132 


ELECTROTYPING. 


rests  on  a  straightedge  of  hard  wood  extending  the 
entire  length  of  the  machine.  The  ends  of  the  hard- 
wood slide  are  supported  by  spring  studs,  which  hold 


Fig.  36. 

the  handle-bar  carrying  the  spindle  high  enough  from 
the  table  so  that  the  cutting  tool  clears  the  work  when 
not  in  operation.  A  pedal  attached  to  a  lever  under- 
neath the  machine  affords  a  means  of  compressing  the 
springs,  thereby  permitting  the  tool  to  enter  the  work. 


ELECTROTYPING.  133 

The  tool  spindle  is  adjustable  in  a  vertical  direction  f:o 
provide  for  plates  of  different  thicknesses,  as  when  a 
change  from  type-high  to  plate  work,  or  vice  versa,  is 
desired.  This  adjustment  is  obtained  by  means  of  a 
hand  wheel  attached  to  a  threaded  sleeve  in  which  the 
spindle  turns.  The  sleeve  is  provided  with  a  feather  to 
prevent  its  turning,  so  that  a  movement  of  the  hand 
wheel  in  either  direction  raises  or  lowers  the  spindle. 
The  work  is  held  in  screw  clamps,  which  slide  freely  in 
dovetailed  grooves  planed  in  the  bed  of  the  machine. 
Power  is  transmitted  to  the  tool  spindle  by  a  belt  passing 
over  idle  pulleys  at  the  corner  of  the  machine.  The 
pulleys  at  the  pivotal  points  of  the  radial  arms  enable 
the  operator  to  move  the  spindle  freely  in  any  direction 
without  changing  the  tension  of  the  belt.  To  perform 
smooth  and  rapid  work  router  tools  require  to  be  driven 
at  a  high  speed.  For  electrotype  metal  the  speed 
should  be  about  12,000  revolutions  per  minute.  A 
machine  running  so  rapidly  should,  of  course,  receive 
careful  attention.     The  bearings  should  be  kept  clean 


Fig.  37. 

and  well  oiled,  and  must  not  be  permitted  to  become 
overheated.  Router  tools  for  general  work  are  about 
the  size  of  a  lead  pencil.  For  special  work  they 
may  be  made  as  small  as  one-sixteenth  of  an  inch 
in  diameter,  and  when  large  quantities  of  metal  are  to 
be  removed,  the  size  of  the  tool  may  be  increased  to 
one-half  inch.     The  cutting  end  of  the  tool  is  made  in 


134 


ELECTROTYPING. 


the  shape  of  a  half  moon,  as  shown  in  Fig.  37,  the 
leading  point  being  slightly  longer  than  the  heel,  to  pre- 
vent clogging.  This  tool  is  sharpened  by  grinding  the 
end  only,  and  may,  therefore,  be  easily  kept  in  order. 
Book  plates,  when  finished  ready  for  the  press,  are 
usually  mounted  on  patent  blocks,  and  are  secured  to 


Fig.  38. 


ELECTROTYPING.  135 

their  bases  by  bevel  clamps  which  lap  over  the  edges  of 
the  plates.  It  is,  therefore,  necessary  to  provide  a  bev- 
eled edge  for  the  plates.  This  work  may  be  performed 
on  a  shootboard  by  using  a  suitable  plane;  but  when  a 
large  number  of  plates  are  to  be  prepared,  it  is  cus- 
tomary to  employ  a  beveling  machine  —  Fig.  38.  This 
machine  resembles  a  trimmer,  but  has  an  adjustable 
vertical  shaft.  It  has  a  reciprocating  carriage  to  carry 
the  work  past  the  cutters,  is  provided  with  gauges  for 
the  alignment  of  the  work,  and  may  be  adjusted  so  as 
to  produce  either  a  rabbet  or  bevel,  as  may  be  desired. 


136  ELECTROTYPING. 


CHAPTER   XVIII. 

REVISING. 

AFTER  book  plates  have  been  straightened,  shaved 
.  and  beveled,  a  proof  is  taken,  and  it  sometimes 
happens  that  errors  or  omissions  are  then  discovered 
which  make  changes  and  corrections  necessary.  Such 
changes  may  consist  in  some  cases  of  only  a  single  let- 
ter, while  in  others  an  entire  line  or  paragraph  may  be 
involved.  In  the  former  case,  the  defective  letters  are 
punched  out  and  type  inserted  in  their  places,  and  in  the 
latter,  the  line  or  paragraph  is  set  up  and  electrotyped, 
and  after  cutting  out  the  defective  portion  of  the  plate 
the  new  piece  is  set  in  and  soldered.  The  special  tools 
required  for  this  work  consist  of  a  set  of  punches  and 
chisels  and  a  pair  of  calipers,  such  as  have  been  pre- 
viously described;  a  revising  stick  (Fig.  39),  a  blow 
pipe,  a  pair  of  cutting  pliers,  a  soldering  iron,  some  small 
flat  files,  and  a  light  hammer.  A  complete  set  of  chisels 
and  punches  consists  of  eight  sizes,  and  corresponds 
with  the  different  sizes  of  type  in  general  use,  namely: 
pica,  small  pica,  long  primer,  bourgeois,  brevier,  minion, 
nonpareil  and  agate.  The  thickness  of  the  tools  corre- 
sponds with  that  of  the  letter  i  in  the  respective  fonts. 
The  revising  stick  may  be  made  of  a  piece  of  print- 
ers' brass  rule,  six  or  more  inches  in  length.  To  one 
edge  and  one  end  of  the  rule  a  strip  of  brass  one-eighth 


ELECTROTYPING. 


137 


of  an  inch  square  should  be  soldered,  as  shown  in  Fig. 
39.  This  makes  a  convenient,  and  in  fact  indispensable 
tool  for  holding  a  line  of  type  while  fitting  it  to  the  slot 
in  the  plate  in  which  it  is  to  be  soldered. 


Fig.  39. 

A  line  gauge,  Fig.  40,  is  employed  for  detecting 
errors  of  alignment  between  the  inserted  type  and  the 
remainder  of  the  line,  and  is  also  employed  for  the 
alignment  of  newspaper  headings  or  other  jobs  com- 
posed of  capitals  and  lower-case  letters.  In  trimming 
a  line  composed  of  a  capital  letter  followed  by  several 
lower-case  letters,   the  width  of  the  block,  of  course, 


Fig.  40. 


must  correspond  with  the  width  of  the  capital,  and  it  is 
obvious  that  without  a  guide  it  would  be  difficult  to 
trim  the  block  so  that  the  lower-case  letters  would  all 
be  at  an  equal  distance  from  the  top  and  bottom  of  the 
block.     The  same  difficulty  would  occur  in  trimming 


138 


ELECTROTYPING. 


any  kind  of  a  job  requiring  a  margin  above  and  below 
the  matter.  The  Une  gauge  enables  the  operator  to 
trim  the  edges  of  such  jobs  exactly  parallel  with  the 
printing  face,  and  is,  therefore,  an  important  and  almost 
indispensable  tool.  When  used  in  revising,  the  edge  of 
the  gauge  is  set  in  alignment  with  the  line  in  which  a 
correction  is  to  be  made.  After  the  type  has  been 
inserted,  and  before  it  has  been  permanently  secured  by 
soldering,  an  application  of  the  gauge  will  determine 
whether  the  alignment  is  perfect. 

The  blowpipe  is  used  for  soldering  in  places  which 
cannot  be  conveniently  reached  with  a  soldering  iron. 
It  consists  of  a  Y  of  brass  tubing,  one  of  whose  arms  is 
connected  by  a  rubber  tube  with  the  gas  supply.  By 
blowing  in  the  other  arm  of  the  Y  a  stream  of  air  is 
mixed  with  the  gas.  The  point  of  flame  may  be 
directed  and  focused  on  any  desired  point,  however 
small. 

Referring  to  Fig.  41,  it  will  be  observed  that  the 
cutting  ends  of  the  revising  punches  are  provided  with 
V  grooves,  which  give  to  the  tools  two  cutting  edges, 


Fig.  41. 


thus  admitting  of  a  sharp,  clean  cut  through  the  plate 
of  just  the  size  of  the  type  which  is  to  be  inserted.  In 
correcting  a  typographical  error  in  a  plate,  the  workman 
first  marks  with  his  caliper  the  exact   location  of  the 


ELECTROTYPING.  139 

letter  upon  the  back  of  the  plate.  With  a  small  chisel 
a  groove  is  then  planed  at  the  point  marked  by  the 
caliper  to  the  depth  of  about  one-half  the  thickness  of 
the  plate,  A  punch  of  the  proper  size  having  been 
selected,  the  plate  is  turned  over,  face  up,  upon  a  block 
of  wood,  and  with  a  sharp  blow  with  the  hammer  the 
letter  is  punched  out.  Turning  the  plate  over  again, 
face  down  upon  the  finishing  block,  the  type  is  inserted 
in  the  hole,  and  the  contiguous  metal  crowded  against 
it  with  a  chisel  until  it  is  secured  against  dropping  out, 
when  the  face  is  examined  to  see  that  the  inserted  type 
is  in  alignment  with  the  remainder  of  the  line  and  level 
with  the  surface  of  the  plate.  Care  must  also  be 
observed  to  keep  the  type  on  its  feet  —  that  is  to  say,  it 
must  not  lean  from  the  perpendicular.  The  body  of  the 
type  which  has  been  left  projecting  through  the  hole  is 
now  cut  off  with  the  pliers  level  with  the  back  of  the 
plate,  and  the  type  secured  in  its  position  with  a  drop 
of  solder.  It  is  of  course  necessary  to  observe  some 
care,  otherwise  there  would  be  danger  of  melting  the 
surrounding  metal  or  the  type  itself  After  the  type  is 
secured  the  superfluous  solder  is  removed  with  a  chisel 
or  file. 

When  several  consecutive  letters  are  to  be  mserted 
in  the  plate,  the  hole  made  with  the  punch  is  enlarged 
with  chisel  and  file  to  the  size  of  the  correction,  and  the 
type  which  has  been  previously  set  up  in  the  revising 
stick  is  inserted  and  temporarily  secured  as  before. 
Somewhat  more  skill  is  required  to  make  a  correction 
of  this  kind  than  to  insert  a  single  letter,  as  the  slot 
must  be  kept  parallel  and  in  exact  alignment  with  the 
remainder  of  the  line,  and  this  is  a  more  difficult  matter 


140  ELECTROTYPING. 

than  to  punch  a  single  hole  in  the  plate.  When  the 
slot  has  been  made  too  large,  as  sometimes  occurs,  the 
type  is  aligned  by  crowding  the  contiguous  metal  against 
that  side  of  the  type  which  is  above  or  below  the 
line.  When  the  type  has  been  properly  placed  it  is 
usually  partially  secured  by  soldering  before  cutting 
off  the  body;  otherwise  there  would  be  danger  of  dis- 
turbing it. 

When  the  correction  consists  of  several  words  or 
parts  of  lines,  the  matter  is  set  up  and  electrotyped  in 
the  usual  manner.  The  corrected  piece  so  made  is  laid 
on  the  plate  in  the  position  it  is  to  occupy,  and  with  a 
graver  or  other  sharp-pointed  tool  its  exact  outline  is 
transferred  to  the  plate.  A  hole  is  drilled  in  one  corner 
and  the  defective  portion  of  the  plate  cut  out  with  a  jig 
saw  —  Fig.  42.  The  correction  is  then  inserted,  the 
plate  turned  face  down  and  a  drop  of  solder  applied  to 
each  of  the  four  corners.  During  the  operation  of  sol- 
dering, the  plate  and  correction  should  be  firmly  held 
against  the  finishing  block  to  prevent  warping  or  spring- 
ing of  the  pieces,  which  might  otherwise  be  caused  by 
the  heat  of  the  iron.  For  this  purpose  the  cutting  pliers 
may  be  reversed,  the  end  of  one  handle  being  used  to 
hold  the  plate  and  the  other  the  correction. 

A  necessary  part  of  the  equipment  of  an  electrotype 
foundry  is  a  set  of  brass  standards  based  upon  the  print- 
er's  universal  unit  of  measurement,  the  pica.  These 
standards  should  be  twenty-six  in  number,  ranging  from 
one  to  twenty-six  picas  in  length.  The  convenience  of 
such  standards  will  be  apparent  when  it  is  remembered 
that  all  large  type,  such  as  is  employed  for  newspaper 
headings,  etc. ,  is  made  to  occupy  the  space  of  a  certain 


ELECTROTYPING. 


141 


Fig.  42. 


142  ELECTROTYPING. 

number  of  lines  of  pica  and  is  called  6-line  type,  7-line 
type,  etc. 

In  addition  to  the  pica  standards,  the  electrotyper 
should  have  a  type-high  standard,  preferably  made  of 
steel,  about  2  by  3  inches  in  size  and  .919  of  an  inch 
thick.  Such  a  standard  is  useful  not  only  for  testing 
finished  work,  but  also  for  setting  the  knife  of  the  shav- 
ing machine,  for  which  purpose  it  is  placed  on  the  bed 
of  the  shaver  and  the  knife  screwed  down  until  it  will 
just  touch  it. 

Book  plates  are  usually  worked  on  patent  blocks  and 
should  be  shaved  to  exactly  eleven  points  (small  pica) 
in  thickness.  For  testing  this  class  of  work  a  standard 
should  also  be  provided. 


ELECTROTYPING.  143 


CHAPTER  XIX. 

BLOCKING. 

"DOOK  plates  are  usually  worked  on  patent  blocks, 
^-^  with  which  every  large  publishing  house  is  sup- 
plied. These  blocks  are  made  in  some  cases  of  wood, 
but  preferably  of  iron,  accurately  finished  and  provided 
with  clamping  devices  for  securing  the  plate  to  the  base. 
The  best  blocks  are  made  in  sections,  and  may  be 
arranged  and  adjusted  to  fit  various  sizes  of  plates. 
The  clamps  are  beveled  and  made  adjustable  so  that 
they  will  fit  snugly  over  the  beveled  edge  of  the  plates. 

Plates  which  cannot  be  worked  on  patent  blocks  are 
secured  by  screws,  tacks  or  anchors  to  wooden  blocks. 
Mahogany  makes  the  best  blocking  wood,  but  is  rather 
expensive  for  general  work.  Cherry  comes  next,  and  is 
the  wood  most  generally  employed  for  blocks ;  birch  and 
maple  are  also  used  to  some  extent.  Blocking  wood 
may  be  procured  ready  for  use,  kiln  dried,  and  surfaced 
to  proper  thickness;  but  most  electrotypers  prefer  to 
purchase  lumber  in  the  rough  and  dress  it  to  thickness 
as  it  is  required  for  blocking,  thus  avoiding  danger  of 
warping,  which  is  likely  to  occur  when  the  wood  is 
dressed  several  days  in  advance  of  its  use. 

Lumber  which  has  been  thoroughly  dried  in  the 
yard  is  superior  to  kiln  dried  lumber  because  it  is  less 
susceptible  to  changes  of  atmosphere.  When  sufficient 
space  is  available  it  is  always  advisable  to  carry  a  stock 


144 


ELECTROTYPING. 


in  the  foundry,  where  it  soon  becomes  seasoned.  It 
often  happens,  however,  that  well-seasoned  lumber  can- 
not be  procured  and  kiln  drying  then  becomes  neces- 
sary.    By  whatever  process  the  wood  is  dried  it  should 


Fig.  43- 


be  thoroughly  done,  otherwise  the  block  will  warp  after 
the  electrotype  has  been  secured  to  it,  probably  after  it 
has  been  delivered  to  the  printer,  in  which  case  much 
annoyance  and  expense  will  inevitably  result. 


ELECTROTYPING.  145 

Blocking  wood  must  be  surfaced  on  both  sides  and 
with  perfect  accuracy  to  insure  good  printing.  For  this 
purpose  a  rotary  planer,  Fig.  43,  is  almost  indispensa- 
ble. The  peculiar  advantage  of  this  machine  consists 
in  the  fact  that  it  dresses  the  wood  perfectly  flat  and 
level,  no  matter  how  badly  it  may  have  been  warped  or 
sprung  before  planing.  In  this  respect  it  is  far  supe- 
rior to  the  ordinary  wood  planer,  for,  while  the  wood  is 
flattened  by  the  pressure  rollers  during  the  operation  of 
planing,  it  springs  back  to  its  original  shape  on  being 
released. 

Referring  to  Fig.  43,  it  will  be  observed  that  the  cut- 
ting tools  of  the  rotary  planer  are  secured  in  a  revolving 
disk  which  is  made  vertically  adjustable  by  means  of  the 
crank  shown  at  the  top  of  the  machine.  Power  is  com- 
municated to  the  disk  by  a  belt  passing  over  idlers  at  the 
rear  of  the  upright  frame  to  the  pulley  on  the  disk  shaft. 
One  of  these  idlers  is  secured  to  a  shaft  which  carries 
on  its  outer  end  a  grooved  pulley  which  provides  a 
means  of  transmitting  power  to  the  worm  shaft  shown  at 
the  side  of  the  machine.  The  worm  wheel  driven  by 
this  shaft  is  secured  to  a  shaft  passing  under  the  travel- 
ing bed,  and  is  provided  on  its  inner  end  with  a  small 
pinion  which  engages  the  rack  attached  to  the  under 
side  of  the  bed.  By  a  simple  mechanism  which  is  at  all 
times  in  control  of  the  operator,  the  worm  is  thrown 
out  of  gear  at  the  termination  of  the  cut  and  the  bed 
returned  to  its  first  position  by  hand.  The  lumber  is 
held  during  the  operation  of  planing  between  the  jaws 
of  two  clamps,  one  of  which  is  stationary  and  the  other 
connected  with  a  screw  which  terminates  in  the  crank 

handle  shown  at  the  front  of  the  machine.      In  opera- 
10 


146  ELECTROTYPING. 

tion,  the  board  is  placed  between  the  jaws  of  the  clamps 
and  locked  by  means  of  the  crank  mentioned.  The 
board  is  thus  secured  against  springing  or  rocking  while 
its  upper  surface  is  dressed  perfectly  true  and  level. 
The  board  is  then  turned  over  with  its  flat  surface 
against  the  bed  of  the  machine,  and  again  passed  under 
the  cutters,  which  reduce  it  to  the  required  thickness. 
The  disk  is  raised  and  lowered  by  a  graduated  adjust- 
ing screw  operated  by  the  crank  shown  at  the  top  of  the 
machine,  and  may,  therefore,  always  be  returned  to  the 
proper  height  for  the  finishing  cut  without  going  to  the 
trouble  of  comparing  each  board  with  a  standard.  Ow- 
ing to  the  large  size  of  the  disk  and  the  fact  that  the 
tools  are  located  near  its  periphery,  the  machine  should 
be  driven  at  a  speed  not  exceeding  1,500  revolutions 
per  minute. 

After  planing,  the  boards  are  cut  into  convenient 
lengths  for  handling,  and  the  plates  secured  to  them 
by  means  of  wire  brads  or  screws,  or  both.  Brads 
may  be  driven  through  the  thin  places  (spaces)  in  the 
plates,  but  for  the  screws  holes  should  be  drilled  and 
countersunk  in  order  that  the  heads  may  be  sufficiently 
depressed  to  avoid  danger  of  blacking  or  smutting  in 
printing.  Where  a  plate  has  no  spaces  or  blanks  where 
brads  or  screws  may  be  driven,  it  is  customary  to 
"anchor"  the  plate  to  the  block.  For  this  purpose 
holes  about  one-fourth  of  an  inch  in  diameter  are  bored 
through  the  block  and  deeply  countersunk  on  both 
sides.  If  the  plate  has  been  finished  long  enough  to 
have  become  oxidized,  the  back  should  be  brightened 
by  filing,  and  is  then  laid  on  the  block  and  temporarily 
secured  thereto  by  hand  clamps.    It  is  then  turned  over 


ELECTROTYPING.  147 

on  its  face,  and,  after  a  very  small  quantity  of  soldering 
fluid  has  been  applied  to  the  plate  through  the  holes, 
melted  solder  is  poured  in  until  the  holes  are  full.  It  is 
important,  of  course,  not  to  get  the  solder  too  hot,  as 
in  that  case  there  would  be  danger  of  its  melting 
through  the  plate.  There  is  always  an  element  of 
uncertainty  in  securing  electrotypes  to  blocks  by  this 
method,  and,  when  possible,  it  is  best  as  an  additional 
safeguard  to  rabbet  the  edges  of  the  plate  and  drive  in 
a  few  brads.  When  the  plate  is  small,  it  may  some- 
times be  fastened  securely  in  this  way  without  the  use 
of  anchors. 

When  several  small  cuts  are  to  be  blocked  at  one 
time,  it  is  customary  to  tack  them  on  to  a  board  as 
large  as  may  be  conveniently  planed,  leaving  sufficient 
room  between  the  cuts  to  saw  them  apart.  Should  it 
be  necessary  to  take  a  final  shaving  off  the  bottom  of 
the  cuts  after  they  have  been  blocked,  it  may  be  done 
more  economically  if  several  are  shaved  at  a  time  than 
if  each  one  were  to  be  handled  separately. 

Very  large  blocks  are  liable  to  warp  in  time,  in  spite 
of  any  precautions  which  may  be  taken  to  prevent  it, 
and  to  reduce  this  tendency  to  a  minimum  each  block 
should  be  strengthened  by  end  strips  crossing  the  grain 
of  the  block.  The  strips  may  be  secured  to  the  blocks 
by  countersunk  screws,  but  a  more  satisfactory  method 
is  to  dovetail  them  together.  A  machine  specially 
designed  for  this  work  is  illustrated  in  Fig.  44.  The 
cutting  tools  are  a  thick  gouge  saw  of  about  No.  3 
gauge,  which  cuts  a  slot  in  the  board  or  strip,  and  a 
vertical  revolving  cutter,  which  follows  in  the  slot  and 
changes  it  into  a  dovetail  groove.     The  mechanism  for 


148 


ELECTROTYPING. 


driving  the  tools  is  sufficiently  explained  by  the  engrav- 
ing. The  parallel  side  gauge,  against  which  the  board 
is  pressed  during  the  cutting  of  the  dovetail,  can  be 
instantly  changed  by  means  of  the  small  lever  at  the 


Fig.  44. 


ELECTROTYPING.  149 

right  of  the  machine  so  that  either  the  center  or  the 
edge  of  the  strip  may  be  thrown  in  alignment  with  the 
cutters,  thus  providing  a  means  of  cutting  a  dovetail  in 
one  board  and  a  tenon  on  the  other.  The  mechanism 
for  changing  the  side  gauge  from  one  position  to  the 
other  is  such  that  there  can  be  no  variation  in  the  dis- 
tance it  is  moved,  and  whatever  position  it  occupies  it 
is  automatically  locked  therein,  thus  insuring  absolute 
uniformity  of  work.  The  machine  may  be  readily 
adjusted  to  operate  on  lumber  of  different  thicknesses. 


150  ELECTROTYPING, 


CHAPTER    XX. 
DR.  Albert's  metal  molds. 

THE  subject  of  metal  molds  is  one  in  which  all 
progressive  electrotypers  are  interested,  and  we 
have  therefore  translated  from  the  German  Dr. 
Albert's  description  of  his  process,  which  is  sufficiently 
in  detail  to  enable  the  skilled  electrotyper  to  compre- 
hend how  it  is  possible  to  mold  in  lead.  Dr.  Albert 
does  not  explain  the  nature  of  the  mechanism  by  which 
he  is  able  to  obtain  "  successive  partial  pressures  "  on 
"  any  press,"  nor  does  he  describe  fully  the  character 
of  the  alloy  which  he  employs  in  loosening  the  shell 
from  the  matrix.  The  American  patents  concerning 
Dr.  Albert's  process  have  been  purchased  by  an  Ameri- 
can manufacturer  of  electrotyping  machinery,  who  has 
already  installed  several  plants  in  this  country  which 
are  in  more  or  less  successful  operation.  The  follow- 
ing is  a  translation  from  "  Theory  and  Practice  of  the 
Metal  Matrix,"  by  Dr.  E.  Albert : 

"  Jacobi,  the  inventor  of  the  art  of  electrotyping, 
has  for  more  than  half  a  century  experimented  in  pro- 
ducing lead  matrices  for  engraved  steel  and  copper 
plates,  and  with  the  greatest  success.  Nevertheless, 
the  wax  and  gutta-percha  matrix  has  been  the  popular 
method  of  electrotyping  until  recently,  although  the 
defects  of  the  electrotypes  made  from  it  urgently  called 
for  a  change  in  the  method. 


ELECTROTYPING.  151 

"  The  origin  of  these  defects  is  to  be  found  princi- 
pally in  the  fact  that  the  non-conducting  material  must 
first  be  made  conductive  by  brushing  with  black  lead, 
whereby  it  is  impossible  to  avoid  an  essential  deterio- 
ration in  quality  as  compared  with  the  original ;  and 
that  in  consequence  of  the  necessary  heating  of  the 
material  before  the  impression  is  taken,  and  the 
changes  in  its  dimensions  after  cooling,  an  exact  regis- 
ter of  electrotypes  for  multi-colored  prints  can  not  be 
guaranteed.  With  the  possibility  of  using  conducting 
and  cold-molded  metal  matrices,  all  this  inferiority  of 
the  electrotypes,  as  compared  with  the  original,  is  at 
once  removed. 

"  But  modern  printing  forms,  such  as  photoengra- 
vings, woodcuts,  type  forms,  heliogravure,  can  not  be 
impressed  in  soft  metal  in  the  same  manner  as  in  wax 
and  gutta-percha.  The  requisite  pressure  would  be 
so  great  that  the  soft  printing  material  would  be 
destroyed. 

"  Some  attempts  to  avoid  the  high  pressure  in  pro- 
ducing metal  matrices  by  using  very  thin  lead  foils 
and  putting  on  them  layers  of  thoroughly  saturated 
pasteboard,  or  wax,  have  never  had  any  practical 
results,  although  they  date  back  to  the  forties  in  the 
last  century,  and  for  the  following  reasons : 

"  Every  electrotyper  knows  that  in  molding  from 
mixed  type  and  cut  forms  the  type  is  impressed  long 
before  the  shading  of  the  woodcut  or  a  photoengraving 
is  molded.  The  above-mentioned  thoroughly  satu- 
rated pasteboard  affects  the  impression  just  as  wax  or 
gutta-percha  made  soft  by  heating,  i.  e.,  the  lead  foil 
must  first  be  pressed  into  the  large  and  then  into  the 


152  RLECTROTYPING. 

smallest  depressions  of  the  printing  form  by  the  satu- 
rated pasteboard.  In  spite  of  the  enormous  ductility 
of  lead,  it  will  not,  of  course,  satisfy  this  demand  for 
expansion. 

"  It  must  be  considered  that  in  the  square  milli- 
meter of  a  photoengraving  there  are  thirty-six  depres- 
sions into  which  the  lead  foil  must  be  pressed,  and 
that  it  applies  itself  to  144  side  walls  per  qmm.  In 
underetched  printing-plates  considerable  force  is  nec- 
essary to  separate  the  matrix  from  the  plate,  and, 
therefore,  it  is  impossible  in  larger  forms, ""without  dis- 
torting the  mold,  to  separate  the  plate  from  the  lead 
foil,  which,  in  the  interest  of  lessening  the  pressure, 
must  be  very  thin. 

"  The  pressure  necessary  for  forcing  any  molding 
material  into  the  smallest  depressions  of  a  form  can 
not  be  produced  as  long  as  an  opportunity  remains  for 
it  to  make  its  way  into  open  spaces.  In  consequence 
of  this  characteristic,  all  wax  matrices  must  be  sub- 
jected to  a  shaving  process  to  remove  the  large  angu- 
lar protuberances,  which  correspond  to  the  depressions 
in  the  printing  form.  This  necessary  manipulation 
would,  of  course,  be  impossible  in  matrices  consisting 
of  thin  lead  foil,  and  also  for  these  reasons  the  use  of 
this  method  for  rule  etching,  woodcuts  and  type  mat- 
ter is  excluded. 

"  It  has  been  pointed  out  as  a  characteristic  of  the 
materials  hitherto  used  for  the  production  of  matrices 
that  the  molding  of  the  largest  depressions  is  done 
before  that  of  the  smallest.  With  soft  metals,  espe- 
cially lead,  the  contrary  is  the  case,  as  this  material 
first  shifts  in  the  direction  of  the  pressure  and  fills  the 


ELECTROTYPING.  153 

small  depressions.  With  increased  pressure,  which  is 
necessary  in  order  also  to  press  the  lead  down  in  the 
large  depressions  of  the  form,  the  lead  also  begins  to 
shift  like  wax  to  the  sides  in  the  neighborhood  of  the 
first-molded  parts. 

"Apart  from  the  fact  that  the  already  molded  little 
points,  which  correspond  to  the  smallest  depressions  in 
the  form,  will  be  shaved  off,  this  shifting  of  the  lead 
has  another  disadvantage,  namely,  that  the  lead  lodges 
in  these  smallest  depressions  and  the  original  will  be 
made  unfit  for  use  through  this  filling  up  with  lead. 
Besides,  neither  type  matter  nor  cuts  will  withstand 
the  enormous  pressure  that  must  be  used  to  impress  a 
lead  plate  of  at  least  five  millimeters  (about  one-fifth 
of  an  inch)  thickness  into  the  large  depressions. 

"  But  such  a  thickness  in  the  lead  plate  would  be 
just  as  necessary  as  in  the  wax  or  gutta-percha,  as  the 
difference  in  height  between  the  face  of  the  type  and 
that  of  the  spacing  is  about  one  pica. 

"  With  the  present  means,  therefore,  matrices  can 
not  be  produced  in  metal  plates,  and  it  has  been  neces- 
sary to  use  wax  or  gutta-percha  for  this  purpose,  until, 
in  the  year  1903,  Dr.  Albert  succeeded  in  establishing 
a  method  for  the  rational  production  of  metal  matrices. 
This  method  is  based  on  a  number  of  inventions  and 
is  patented  in  all  civilized  countries. 

"  The  knowledge  that  depressions  in  the  electro- 
types in  the  blank  spaces  are  required  only  to  prevent 
smearing  in  the  subsequent  printing  of  the  electro- 
types, led  to  the  course  of  pressing  or  bending  a  lead 
plate  of  about  two  millimeters  (about  seventy-eight 
one-thousandths  of  an  inch)  thickness  into  said  depres- 


154 


ELECTROTYPING. 


sions  only  so  far  as  the  technical  necessities  of  printing 
demanded,  by  means  of  a  backlayer  of  some  soft 
material. 

"  This  method  is  accordingly  based  upon  a  com- 
bination of  impression  and  bending.  The  bending  of 
the  lead  will  be  greater  the  larger  and  wider  the 
depressed  surface  is,  and  the  blank  places  will  there- 
fore be  of  such  a  depth  that  they  will  not  smear  in 
printing.    The  process  is  illustrated  by  Figs,  i  and  2. 

"  Fig.  I  shows  the  arrangement  of  the  press  platen, 
the  lead  plate  and  the  soft,  elastic  intermediate  layer 


Fig.    I. 


before  the  impression  is  taken.  The  material  used  for 
this  purpose  must  originally,  or  in  its  arrangement,  be 
of  certain  qualities,  and  must  be  softer  than  the  mold- 
ing material.  It  must  be  compressible  without  giving 
way  sideward  under  the  pressure ;  but  it  must  also 
give  a  certain  resistance  to  the  compression  in  order  to 
be  able  by  this  power  of  resistance  to  bend  the  lead 
plate  where  it  lies  over  the  hollow.  This  material, 
however,  should  not  be  so  soft  as,  for  example,  heated 
wax,  but  should  be  porously  soft,  either  in  its  nature 
or  in  its  arrangement.  A  certain  degree  of  elasticity 
is  useful  in  the  interest  of  the  bending  of  the  molding 
plate  into  the  depressions  in  the  form. 


ELECTROTYPING, 


155 


"  Such  intermediate  layer  can  suitably  consist  of  a 
number  of  layers  of  paper,  and  such  a  one  is,  through 
the  nature  of  the  fiber  of  the  paper,  as  well  as  through 
the  air  inclosed  between,  soft  and  elastic  in  itself  in 
respect  to  the  vertical  direction  toward  the  surface  of 
impression ;  while,  on  the  other  hand,  through  the 
texture  of  the  paper,  the  necessary  check  will  be  given 
to  prevent  the  paper  from  gliding  sideways  at  the 
beginning  of  the  pressure.  In  earlier  experiments  the 
latter  tendency  was  prevented  by  saturating  the  paper. 

"  In  Fig.  2  the  platen  is  lowered  so  that  the  inter- 
mediate layer  between  the  points  o  o',  from  which  the 
first  counterpressure  comes,  is  compressed  to  half  its 
original  volume.    In  the  moment  when,  through  com- 


FlG.    2. 


pression,  the  intermediate  layer  has  reached  the  same 
degree  of  hardness  as  the  molding  material,  the  next, 
increase  in  pressure  will  press  this  material  into  the 
smallest  depressions  of  the  surface  o  o'.  The  lead 
lying  perfectly  free  between  the  points  u  u',  and  there- 
fore exerting  no  counterpressure,  will  simultaneously 
be  pressed  down  in  the  hollow  space  u  u'  as  an  effect 
of  the  resisting  power  of  the  intermediate  layer. 

"  The  same  will  be  the  case  between  the  points 
m  m',  although  in  a  lesser  degree,  just  as  a  board  that 


156  ELECTROTYPING. 

is  supported  at  intervals  of  two  meters  will  sag  more 
than  one  whose  supports  are  only  one  meter  apart, 
with  the  same  weight  on  it. 

"  By  the  use  of  this  bending  i)rocess,  the  requisite 
molding  pressure  is  reduced  to  one-tenth  of  what 
would  otherwise  be  necessary,  and  the  use  of  metal 
molds  is  made  possible. 

"  The  question  of  producing  the  metal  matrix  was 
thus  solved  only  for  moderate  sizes,  for,  even  if  the 
pressure  was  considerably  lessened  by  the  correct  selec- 
tion of  the  thickness  of  the  lead  plate  and  by  the  back- 
layer  of  a  soft,  elastic  matter,  still  an  essentially  greater 
pressure  than  is  required  for  wax  or  gutta-percha  is 
necessary.  The  usual  hydraulic  presses  with  about 
one  hundred  atmospheres  were  consequently  not  usable 
for  the  impression  of  larger  sizes. 

"  By  using  a  successive  partial  pressure  and  at  the 
same  time  introducing  a  secondary  pressure,  Dr. 
Albert  has  succeeded  in  changing  any  press  to  a  twenty 
times  higher  capacity  at  very  small  cost.  This  gradual 
progress  of  a  limited  pressure  over  the  whole  form 
affords  an  opportunity  for  the  air  to  escape  and  pre- 
vents troubles  arising  from  this  cause.  As  the  shifting 
proceeds  automatically,  there  is  no  loss  of  time  worth 
mentioning  in  this  method.  For  example :  The  mold- 
ing of  a  form  of  Woche  (the  Week)  requires  only  a 
period  of  fifty-five  seconds,  and  for  a  form  of  Berliner 
Illustrirte  Zeitting  (Berlin  Illustrated  Gazette)  not 
quite  two  minutes.  For  molding  of  cut  forms  of  the 
same  size  only  half  of  the  time  mentioned  is  required. 
With  this  method  there  is  no  difficulty  whatever  in 
producing  molds  of  any  size. 


ELECTROTYPING.  157 

"  It  is  self-evident  that  a  copper  shell  deposited  on 
a  lead  matrix  can  not  be  loosened  directly,  as  is  the 
case  with  a  wax  matrix.  It  would  not  be  possible  to 
melt  the  lead  away  from  the  copper  without  injury  to 
the  electrotype.  But  by  letting  the  matrix  and  copper 
deposit  float  on  a  very  easily  fusible  metal  alloy  with 
many  free  calorics,  this  loosening  succeeds  so  well  that 
the  same  matrix  can  be  used  five  times  for  the  produc- 
tion of  new  electrotypes  without  affecting  the  quality 
of  the  electrotypes.  Thus  the  problem  of  the  metal 
matrix  is  perfectly  solved  in  all  respects. 

"  These  inventions  have  made  a  revolution  in  elec- 
trotyping  technics.  The  word  revolution,  however,  has 
more  reference  to  the  clearness,  rapidity,  cheapness 
and  quality  of  the  production  than  to  the  change  of 
the  working  methods  and  arrangements  of  already 
established  electrotype  foundries. 

"Of  great  importance  is  the  discarding  or  doing 
away  with  the  blackleading  of  the  mold  matrix, 
whereby  in  soft  printing  elements  of  photoengravings, 
etc.,  a  shifting  of  the  tone  values  in  respect  to  the 
original  occurs.  The  metal  matrix  in  itself  conducts 
the  electricity  and  needs  no  blackleading. 

"  The  Albert  electrotype  is  identical  with  the  origi- 
nal. A  difference  in  the  print  of  both  can  not  be 
detected.  This  identity  of  the  Albert  electrotype  and 
the  original,  in  respect  to  the  tone  values,  is  based  on 
the  nature  of  the  metal  matrix  and  is  not  dependent 
on  the  skill  of  the  workman. 

"  The  molding  process  itself  can  be  done  on  any 
hydraulic  press  in  use.  The  machinery  for  successive 
partial  pressure  can  be  set  up  in  a  few  hours  at  a  small 


158  ELECTROTYPING. 

expense.  The  increase  of  the  capacity  of  the  press  is 
enormous  ;  with  120  atmospheres  (1,800  pounds  to  the 
square  inch),  with  40  centimeters  piston  diameter 
(about  16  inches)  photoengravings,  40  by  50  centi- 
meters ( 16  by  20  inches)  large,  can  be  molded.  Faulty 
moldings,  as  in  wax,  which  are  occasioned  by  inclosed 
air,  do  not  generally  occur,  as  the  air  always  has  a 
chance  to  escape  during  the  successive  partial  pressure. 

"  It  has  already  been  mentioned  how  little  time  is 
necessary  for  successive  partial  pressure  when  suitable 
arrangements  are  made.  Wax  and  gutta-percha  have 
not  only  to  be  blackleaded  after  molding,  but  by  heat- 
ing be  brought  to  a  certain  degree  of  softness  before 
molding.  In  this  way  changes  in  the  dimensions  arise 
when  the  molds  cool  off,  and  exact  register  can  there- 
fore not  be  guaranteed  in  electrotypes  for  multi- 
colored prints.  The  metal  matrix  is  perfectly  cold- 
molded,  and  therefore  an  exact  register  in  multi- 
colored prints  is  always  assured. 

"  Thus  the  metal  matrix  is  cleaner  and  more  rapid 
than  wax  or  gutta-percha,  and,  besides,  is  of  a  quality 
that  guarantees  the  identity  of  the  electrotypes  with 
the  original.  The  financial  advantages  of  the  Albert 
electrotype  will  be  seen  in  the  further  manipulation  of 
the  matrix. 

"After  the  lifting  off  of  the  form,  the  matrix  will, 
without  any  afterwork  whatever,  be  fastened  with  four 
nails  to  a  board,  whose  suspending  bow  touches  the 
matrix  by  contact,  and  the  latter  will  at  once  be  coated 
over  the  whole  surface  with  copper  in  the  same 
moment  it  is  suspended  in  the  bath.  Owing  to  the 
high  melting-point  of  the  matrix,  the  copper  bath  can, 


ELECTROTYPING.  159 

without  any  danger  to  the  matrix,  be  heated  to  50°  to 
60°  Celsius  (which  will  allow  an  increase  in  the  cur- 
rent tension  of  eight  to  twelve  volts),  and  the  forma- 
tion of  a  sufficiently  thick  copper  deposit  will  follow  in 
a  hitherto-considered  impossible  short  time ;  for 
medium  sizes  only  one-half  to  one  hour  for  producing 
the  deposit  is  needed. 

"  Besides  this  shortening  of  the  time  for  producing 
the  deposit,  the  high  temperature  will  act  favorably 
on  the  physical  character  of  the  electrically  deposited 
copper,  as  well  in  respect  to  its  hardness  as  to  its  elas- 
ticity, which  also  is  evident  in  the  fact  that  the  electro- 
types need  only  a  minimum  straightening. 

"  The  loosening  of  the  copper  shell  from  the  metal 
matrix  is  done  so  easily,  rapidly  and  surely  that  no 
damage  to  or  change  in  the  metal  matrix  or  copper 
shell  results.  The  matrix  can  therefore  at  once  be 
suspended  in  the  bath  again  for  a  second  copper 
deposit,  and  this  second  electrotype,  as  well  as  the 
third  and  fourth,  is  in  no  way  inferior  to  the  first  elec- 
trotype. 

"  When  the  matrix  is  not  to  be  used  any  more,  it 
can  be  converted  into  backing  metal.  The  loosened 
copper  shell  can,  of  course,  be  backed  in  any  way 
desirable,  and  the  electrotype  be  made  ready  for  print 
in  the  usual  way.  Only  one  hour  and  a  half  is  needed 
(inclusive  of  the  molding  and  copper  deposit)  for  put- 
ting the  electrotype  in  shape  for  the  press." 


REFERENCE   LIST 

OF  TERMS,  PROCESSES  AN-D  APPARATUS. 


ACID,  TO  ASCERTAIN  PERCENTAGE  OF,  IN 
SOLUTION. —  Dilute  lo  grams  of  the  solution  with  an  equal 
quantity  of  distilled  water.  Add  normal  soda  solution  until 
Congo  paper  is  no  longer  colored  blue.  The  number  of  grams 
of  soda  solution  consumed  multiplied  by  4.9  gives  the  number 
of  grams  of  acid  per  liter.    One  liter  equals  1,000  grams. 

ACID,  EFFECT  OF,  ON  NICKEL  BATH.— The  pres- 
ence of  a  small  quantity  of  free  acid  in  the  nickel  bath  effects 
the  reduction  of  a  whiter  nickel  than  in  the  case  with  a  neutral 
or  alkaline  solution.  Hence  a  slightly  acid  reaction  of  the  bath 
due  to  the  presence  of  citric  acid,  with  the  exclusion  of  the 
strong  acids  of  the  metalloids,  can  be  highly  recommended. 
The  quantity  of  free  acid  must,  however,  not  be  too  large,  as 
this  would  cause  the  deposit  to  pull  off. 

ACID,  EFFECT  OF,  IN  SOLUTION.— According  to 
Von  Hubl,  the  minimum  current  density  per  square  foot  of 
cathode  in  a  fifteen  per  cent  blue  vitriol  solution  without  acidu- 
lation  is  24.1  amperes,  while  the  same  solution  with  six  per 
cent  sulphuric  acid  added  required  but  13.9  amperes. 

ACID,  HYDROCHLORIC— The  pure  acid  is  a  colorless 
fluid  which  emits  abundant  fumes  in  contact  with  the  air  and 
has  a  pungent  odor  by  which  it  is  readily  distinguished  from 
other  acids.  The  specific  gravity  of  the  strongest  hydrochloric 
acid  is  1.2;  the  crude  acid  of  commerce  has  a  ycllowi.sh  color, 
due  to  iron,  and  contains  arsenic. 

ACID,  MURIATIC—  See  hydrochloric  acid. 

ACID,  SULPHURIC—  Ordinary  sulphuric  acid  has  a  spe- 
cific gravity  of   1.84.     It  is   used  in  the   preparation   of   the 

11  161 


162  ELECTROTYPING. 

depositing  solution.  In  diluting  the  acid  with  water,  it  should 
in  all  cases  be  added  to  the  water  in  a  gentle  stream  and  with 
constant  stirring,  as  otherwise  a  dangerous  explosion  might 
result.  While  it  is  known  that  sulphuric  acid  aids  in  making 
the  bath  conductive,  there  is,  of  course,  a  limit  to  the  quantity 
which  may  be  advantageously  employed,  and  it  is  doubtful  if 
this  point  has  ever  been  exactly  determined.  The  writer  has 
been  to  some  trouble  to  ascertain  the  views  of  certain  practical 
electrotypers  on  the  subject  and  compared  them  with  the 
recommendations  of  numerous  scientific  writers.  From  these 
various  sources  of  information  we  learn  that  the  solution  of 
copper  should  show  a  specific  gravity  of  from  14°  to  18°  B., 
and  that  to  the  solution  should  be  added  sulphuric  acid  in  suf- 
ficient quantity  to  increase  the  density  of  the  mixture  from 
J4°  to  9°.  This  wide  divergence  of  opinion  is  probably  due  in 
some  cases  to  the  effort  of  the  electrotyper  to  adapt  his  solu- 
tion to  the  current  strength  which  his  dynamo  may  happen 
to  be  generating. 

ACID,  SOLDERING. —  Prepared  by  dissolving  scrap  zinc 
in  hydrochloric  acid  (muriatic  acid)  to  saturation,  and  adding 
from  25  to  50  per  cent  of  water.  The  operation  should  be  con- 
ducted in  the  open  air,  as  the  fumes  produced  are  both  dis- 
agreeable and  dangerous. 

AGITATION,  BENEFITS  OF.— The  continuous  agita- 
tion of  the  copper  bath  is  of  great  advantage  to  the  electro- 
type, particularly  when  rapid  deposition  is  desired.  The  copper 
is  more  evenly  deposited  and  of  better  quality,  the  formation  of 
gas  bubbles,  nodules  and  excrescences  is  largely  prevented, 
while  the  annoying  streaks  which  sometimes  appear  on  the 
deposit,  usually  as  a  result  of  an  excess  of  metal  in  the  solu- 
tion, are  seldom  or  never  seen  in  an  agitated  bath.  But  the 
principal  advantage  may  be  found  in  the  fact  that  much  higher 
current  densities  may  be  utilized,  resulting  in  a  corresponding 
increased  rate  of  deposition. 

AGITATION,  DOES  IT  ELIMINATE  RESISTANCE? 
—  While  agitation  is  a  practical  and  useful  aid  to  deposition  of 
metals,  and  is  recognized  as  such  by  all  electrotypers  who  have 


ELECTROTYPING.  163 

given  it  a  trial,  as  well  as  by  all  the  great  copper  refiners  of 
Europe  and  America,  its  chief  value  consists  in  the  fact  that 
it  promotes  uniformity  in  the  composition  of  the  solution,  aids 
in  the  diffusion  of  metal  in  the  solution,  and,  when  a  strong 
current  is  employed,  prevents  to  a  certain  extent  the  forma- 
tion of  nodules,  excrescences  and  streaks  on  the  cathode.  It 
also  minimizes  the  tendency  to  polarization  and  promotes 
purity  in  the  character  of  the  copper  deposited.  If  inequality 
in  the  composition  of  the  solution  tends  to  increase  the  resist- 
ance of  the  solution,  then  agitation,  by  promoting  uniformity, 
would  diminish  the  resistance  to  just  that  extent.  It  is  doubt- 
ful, however,  whether  the  mere  fact  of  giving  motion  to  a 
solution  adds  to  its  conductivity.  In  other  words,  if  an  agi- 
tator should  be  introduced  into  a  depositing  solution  which 
had  previously  been  employed  for  electrotyping  without  agita- 
tion, and  if  no  change  were  made  in  the  content  of  acid  or 
metal  in  the  solution  or  in  the  speed  of  the  dynamo,  the 
increase  in  the  rate  of  deposition  would  probably  be  inappre- 
ciable. It  should  be  understood  that  some  motion  always  takes 
place  in  the  solution  whenever  deposition  is  going  on.  With- 
out motion  there  could  be  no  diffusion,  and  without  diffusion 
there  could  be  no  deposition,  for  it  is  obvious  that  there  must 
be  constant  renewal  of  metal  in  the  solution  next  the  cathode, 
as  otherwise  it  would  soon  become  exhausted.  This  motion 
is  caused  by  the  sinking  of  the  heavy  liquid  next  the  anode 
and  the  constant  rising  of  the  liquid  next  the  cathode,  where 
it  is  deprived  of  its  metal,  and  consequently  becomes  lighter 
than  the  surrounding  liquid.  This  motion,  together  with  the 
stirring  of  the  solution  occasioned  by  the  immersion  and 
removal  of  the  cathodes,  is  sufficient  for  the  diffusion  of  the 
metal  when  a  current  of  low  density  is  employed.  It  is  true 
that  a  solution  undisturbed  for  some  time  will  become  more 
acid  at  the  top  than  at  the  bottom  and,  therefore,  more  con- 
ductive at  the  top  than  at  the  bottom.  Yet  it  is  doubtful  if 
the  total  resistance  of  the  solution  is  very  much  affected  by 
this  condition.  Granting  that  agitation  would  diminish  the 
resistance  of  the  solution  to  a  slight  extent  by  promoting  uni- 


164  ELECTROTYPING. 

formity,  it  is  certain  that  it  does  not  influence  the  resistance 
beyond  this  point,  for  frequent  tests  have  demonstrated  that 
the  current  strength  measured  at  the  electrodes  remains 
unchanged  whether  the  agitator  be  in  operation  or  not.  But 
if  the  agitator  does  not  in  itself  increase  the  rate  of  deposition, 
it  enables  the  operator  to  increase  his  current  and  thereby 
accomplish  practically  the  same  purpose.  Von  Hubl  found  by 
careful  laboratory  tests  that  the  current  strength  could  be 
increased  about  fifty  per  cent  when  the  bath  is  kept  in  gentle 
motion.  This  statement  is  very  conservative  and  probably 
means  that  the  current  strength  may  be  increased  fifty  per 
cent  without  changing  the  character  of  the  copper  or  causing 
waste  of  power  by  polarization.  If  no  consideration  be  given 
to  economical  working,  there  is  no  doubt  but  the  current  may 
be  increased  far  beyond  the  fifty-seven  amperes  per  square 
foot  which  he  gives  as  a  maximum. 

AGITATION,  METHODS  OF.—  One  of  the  main  objects 
of  agitation  is  to  remove  the  exhausted  stratum  of  solution 
next  to  the  cathode  and  replace  it  with  a  saturated  solution  in 
order  that  deposition  may  proceed  with  the  greatest  possible 
rapidity.  Various  mechanical  means  are  employed  to  effect 
this  object.  The  most  popular  method  is  that  of  forcing  air 
through  the  solution  from  perforated  lead  or  rubber  pipes  laid 
on  the  bottom  of  the  vats.  Another  method  consists  in  pump- 
ing the  solution  from  the  bottom  of  one  end  of  the  vat  and 
discharging  it  in  such  a  manner  as  to  create  a  circular  motion. 
Another  method  consists  in  mounting  the  anodes  on  spindles 
and  revolving  them  slowly  in  the  solution  between  the  cathodes. 
By  another  and  very  effective  method  a  horizontal  rod  is  made 
to  travel  up  and  down  between  the  anode  and  cathode.  The 
latest  and,  it  is  claimed,  the  best  method  is  briefly  described 
as  follows :  A  large  perpendicular  cylinder  is  made  to  revolve 
slowly  in  the  solution.  The  cylinder  is  surrounded  by  anodes 
and  to  the  periphery  of  the  cylinder  the  cathodes  arc  attached. 
In  operation  the  cathodes  are  constantly  passing  the  anodes 
and  the  disturbance  is  so  effectual  that  200  or  more  amperes 
per  square  foot  may  be  utilized  without  burning  the  deposit. 


ELECTROTYPING.  165 

ALKALINITY  AND  ACIDITY.— An  excess  of  acid  or 
alkali  in  a  nickel  solution  may  be  instantly  detected  by  dip- 
ping simultaneously  into  the  solution  strips  of  blue  and  red 
litmus  paper.  If  the  blue  litmus  paper  becomes  red,  it  indi- 
cates an  excess  of  acid,  while  on  the  other  hand  the  test  shows 
that  when  red  litmus  paper  becomes  blue  an  excess  of  alkali 
is  indicated. 

ALLOY,  FUSIBLE.— Melt  i  pound  of  lead  in  a  clean 
vessel,  and  stir  in  %  pound  of  tin  and,  finally,  iJ/S  pounds  of 
bismuth.  Stir  well,  and  thoroughly  incorporate  the  mixture; 
pour  out  gradually  into  water ;  collect,  and  repeat  until  a  com- 
plete admixture  is  obtained.  It  melts  at  212°  F.,  the  tem- 
perature of  boiling  water. 

AMALGAMATION  OF  ZINC— To  amalgamate  zinc 
plates  it  is  necessary,  first,  if  the  plates  be  new,  to  wash  them 
in  hot  caustic  soda  solution,  so  as  to  remove  the  greasy  film 
imparted  to  them  at  the  rolling  mills.  A  flat  vessel  is  then 
partially  filled  with  dilute  sulphuric  acid  and  upon  it  is  also 
poured  a  little  of  the  best  quality  of  mercury  procurable.  The 
plate  is  dipped  in  the  liquid  and  the  mercury  rubbed  on  with 
a  pad  of  tow  or  other  suitable  substance.  The  workman  should 
take  particular  care  to  cover  every  portion  of  the  surface. 
When  the  plates  present  a  uniform  silvery  appearance  they 
may  be  set  upon  edge  to  drain,  after  which  they  are  ready  to 
be  placed  in  the  battery. 

AMMETER?  WHAT  IS  AN.— Without  going  into 
technicalities,  it  may  be  said  that  the  ammeter  is  an  instru- 
ment for  measuring  the  amount  or  quantity  of  electric  current 
employed  in  performing  work.  The  ammeter  measures  quan- 
tity, while  the  voltmeter  measures  pressure,  and  the  product 
of  quantity  multiplied  by  pressure,  as  measured  by  these  instru- 
ments, is  called  watts  and  is  what  we  who  buy  electric  power 
have  to  pay  for  at  the  end  of  each  month. 

AMMETER  VARIATION.— The  ammeter  reading  may 
vary  from  two  causes  on  a  constant  surface  (cathode)  load 
without  the  voltmeter  varying.    The  resistance  of  the  solution 


166  KLF.CTROTYPING. 

may  vary  or  the  resistance  between  the  supporting  or  case 
rods  and  the  tank  rods  may  vary.  Another  reason,  probably 
the  best,  is  that  a  new  case  when  immersed  presents  a  large 
resistance,  due  to  the  lack  of  copper  on  the  surface.  A  new 
case  will  not  use  full  current  density  for  some  minutes  after 
it  is  immersed.  In  fact,  the  current  for  the  first  few  seconds 
is  almost  nothing.  If  you  have  a  large  number  of  fresh  cases, 
and  a  few  that  are  nearly  done,  your  current  will  perhaps 
be  fifty  per  cent  low  with  no  voltmeter  change.  Bad  brush 
contact  would  vary  voltmeter  and  ammeter  together. 

AMMONIA. —  Is  water  saturated  with  ammonia  gas. 
Must  be  stored  in  closely  stoppered  bottles.  It  is  employed 
for  neutralizing  nickel  solutions  when  too  acid  and  is  some- 
times added  to  soldering  fluid. 

AMPERE. —  The  unit  of  current  strength  is  produced  when 

an  electromotive  force  of  one  volt  acts  through  a  resistance 

'  of  one  ohm  and  conveys  one  coulomb  per  second.    An  ampere 

is  that  strength  of  current  which  will  deposit  .00508  grain  of 

copper  per  second  from  a  blue  vitriol  solution. 

ANCHORING  ELECTROTYPES  AND  HALF-TONES. 
—  Bore  several  holes  through  the  base  and  countersink  both 
sides.  If  the  plate  has  been  finished  long  enough  to  have 
become  oxidized,  brighten  the  back  by  filing  and  tlicn  lay  it 
on  the  block  and  secure  it  temporarily  by  hand  clamps.  Apply 
a  small  quantity  of  soldering  fluid  to  the  plate  through  the 
holes  and  then  pour  in  melted  solder  until  the  holes  are  full. 
It  is  important,  of  course,  not  to  get  the  solder  too  hot,  as  in 
that  case  there  would  be  danger  of  melting  through  the  plate. 
There  is  always  an  element  of  uncertainty  in  securing  plates 
by  anchoring,  but  in  some  cases  there  is  no  other  way  to 
accomplish  the  object. 

ANODE. —  The  pole  or  plate  by  which  an  electric  current 
enters  a  depositing  solution.  In  electrotyping  a  solid  plate  of 
copper  of  any  convenient  thickness  and  about  the  same  area 
as  the  cathode  or  mold,  it  should  be  connected  with  the  posi- 
tive pole  of  the  battery  or  dynamo  and  kept  clean  by  occa- 
sional scouring  and  washing. 


ELECTROTYPING.  167 

ANODE  CONNECTIONS.— A  new  anode  connection 
recently  introduced  consists  of  a  broad  strap  of  copper  about 
three  inches  wide  and  one-eighth  of  an  inch  thick,  accurately 
milled  where  it  hooks  over  the  rod  so  as  to  make  a  perfect 
connection.  The  strap  is  secured  to  the  anode  by  a  casting  of 
electrotype  metal  which  covers  and  protects  the  connection 
from  the  action  of  the  solution.  The  anode  may,  therefore, 
be  suspended  entirely  under  the  solution  without  danger  of 
destroying  the  connection,  which  is  practically  everlasting.  In 
addition  to  the  advantage  of  having  a  perfect  connection,  the 
anodes  wear  away  evenly,  leaving  no  stub  ends  to  go  in  the 
junk  pile  or  be  worked  off  in  the  baskets. 

ANODE  HOOKS.— Anode  hooks  should  be  of  ample 
dimensions  to  carry  a  large  volume  of  current  without  heating. 
Copper  wire  of  three-eighths  of  an  inch  in  diameter  is  recom- 
mended. The  hooks  should  be  kept  clean  where  contact  is 
made  with  anodes  and  cross  rods,  to  insure  minimum  resist- 
ance. 

ANODE  PLATES,  SIZE  OF.— The  anode  and  cathode 
should  each  present  an  equal  surface  to  the  solution.  The 
anode  has  two  sides,  but  the  back,  when  facing  flat  work, 
should  be  left  out  of  account.  Hence  an  electrotype  a  foot 
square  should  be  faced  by  an  anode  a  foot  square.  If  there 
be  any  difference  in  size,  the  anode  should  be  the  larger. 

ANTIMONY. —  Antimony  is  hard  and  brittle  and  melts 
at  842°  F.  It  is  not  attacked  by  cold  sulphuric  acid.  It  is 
employed  with  lead  and  tin  in  the  manufacture  of  electrotype 
and  stereotype  metal  to  harden  the  mixture. 

"  BACKER-UP,"  THE.—  Next  to  the  molder,  the  backer- 
up  is  the  most  valuable  man  in  a  first-class  foundry  —  that  is, 
a  good  one  that  knows  his  business  in  regard  to  having  his 
metal  right  and  how  to  pour  it  on  his  shell  with  the  least 
injury  to  the  plate  and  to  avoid  shrinks.  The  responsibility  of 
the  backer-up  is  very  great,  and,  if  he  does  his  work  properly, 
he  can  save  a  great  deal  of  time  and  labor  in  the  finishing 
room. 


168  ELECTROTYPlNC. 

BACKING-UP  PRESS  FOR  ELECTROTYPES.— A 
patented  device  for  backing  up  and  straightening  electrotypes 
consists  of  a  bed  frame  supported  by  suitable  legs  and  made 
long  enough  to  provide  room  at  its  middle  part  for  a  yoke  and 
vertically  adjustable  platen.  At  one  side  of  the  platen  suffi- 
cient space  is  provided  for  the  backing  pan  to  set  during  the 
process  of  backing  up  the  shell,  and  on  the  other  side  there  is 
room  for  moving  the  finished  plate  out  so  that  another  pan 
may  be  placed  in  position  at  the  left  hand  of  the  platen.  The 
yoke  and  platen  are  somewhat  similar  to  the  yoke  and  platen 
of  a  stereotyper's  drying  press,  except  that  the  platen  is  pro- 
vided on  its  under  side  with  a  layer  of  felt  about  one-fourth 
of  an  inch  in  thickness,  and  a  press  plate  having  projections 
or  teats  on  its  surface  called  a  "  hurdy-gurdy "  plate.  The 
hurdy-gurdy  plate,  with  the  intermediate  layer  of  felt,  is 
attached  by  bolts  to  the  platen.  The  bed  frame  is  provided 
with  rollers  to  facilitate  the  passage  of  the  backing  pan  from 
one  end  of  the  bed  to  its  position  under  the  platen,  and  from 
thence  to  the  other  end  of  the  bed.  In  operation,  the  shell  is 
placed  in  the  backing  pan  on  one  end  of  the  press,  where  it 
is  backed  up  and  cooled  in  the  usual  manner.  The  backing 
pan  is  then  rolled  under  the  platen  and  pressure  applied  by 
means  of  a  hand  wheel  and  screw,  which  has  the  alleged  effect 
of  straightening  the  face  of  the  electrotype  and  bringing  all 
parts  of  the  same,  by  means  of  the  hurdy-gurdy,  into  one 
plane,  removing  all  unevenness  and  irregularities.  It  is 
claimed  the  intermediate  layer  of  yielding  material  permits  the 
hurdy-gurdy  to  give  and  adapt  itself  so  it  will  not  press  any 
harder  on  the  ends  or  sides  of  the  electrotype  than  on  the 
intermediate  points.  The  inventor  asserts  that  a  great  saving 
of  time  is  accomplished  by  this  method  of  straightening  plates, 
as  very  little  finishing  is  required. 

BLACKLEADING  BY  HAND.—  Blackleading  by  hand  is 
a  slow  and  laborious  process  and  is  seldom  practiced,  a  machine 
being  considered  essential  even  in  small  foundries.  For  black- 
leading  by  hand,  a  camel's-hair  brush  is  employed.  The 
graphite  should  be  brushed  back  and  forth  over  the  mold  until 


ELECTROTYPING.  169 

a  bright  polish  is  obtained  and  until  it  is  certain  that  no  spot, 
however  small,  has  been  neglected.  If  so  much  as  a  punctua- 
tion point  fails  to  receive  the  proper  polish,  copper  will  not 
deposit  thereon,  and  a  hole  in  the  shell  will  result.  In  the 
days  before  blackleading  machines  were  invented,  it  was  the 
custom  to  place  the  mold  in  a  box  provided  at  the  front  with  a 
curtain.  Then,  by  inserting  the  hand  through  a  hole  in  the 
curtain,  the  polishing  could  be  effected  without  filling  the  air 
of  the  room  with  dust. 

BLACKLEADING  MACHINE,  WET.— The  only  wet 
leading  machine  is  the  one  patented  about  twenty-six  years 
ago  by  Mr.  S.  P.  Knight,  foreman  of  the  electrotyping  depart- 
ment of  Harper  Brothers.  The  machine  consisted  of  a  tank 
with  a  centrifugal  pump,  to  which  there  was  attached  a  hose 
and  syringe.  The  tank  contained  a  mixture  of  plumbago  and 
water,  of  about  the  consistency  of  cream,  which  by  means  of 
the  pump,  was  forced  through  the  syringe,  which  was  arranged 
to  move  to  and  fro  across  the  tank  and  thus  coat  the  molds, 
which  were  laid  on  a  rack  placed  just  below  the  surface  of  the 
solution  in  the  tank.  On  moving  the  cases  from  the  machine, 
the  surplus  mixture  was  scraped  oflf  with  the  hand,  the  cases 
being  afterward  thoroughly  washed  in  another  tank.  The 
plumbago  in  the  second  tank  was  allowed  to  settle  before  the 
water  was  drawn  off.  This  process  gave  promise  of  obviating 
much  dust  in  the  foundry,  but  never  came  into  extensive  use 
owing  to  the  inability  of  workmen  to  operate  it  successfully, 
notwithstanding  that  Mr.  Knight  used  it  and  no  other  method 
for  coating  his  molds.  In  use  it  was  found  that,  from  the  drip- 
pings from  the  cases  after  the  water  had  dried  out,  there  was 
nearly  as  much  dust  in  the  room  as  with  the  dry  process. 

BLISTER  ON  SHELLS.—  Blister  is  sometimes  caused  by 
an  excess  of  crocus  on  the  mold ;  it  will  cause  shrinks  in  the 
plates,  making  trouble  for  the  finisher.  Crocus  should  be  used 
very  sparingly,  if  at  all,  and  should  be  carefully  brushed  off 
the  mold  before  it  goes  into  the  vat.  Instead  of  crocus,  brush 
a  small  quantity  of  sulphate  of  zinc  on  the  case  before  molding. 


170  ELECTROTYPING. 

BOOK-PLATES,  DEVICE  FOR  HOLDING.— When 
molding  from  beveled  book-plates,  make  four  wooden  blocks 
exact  size  of  the  book-plates  which  arc  to  be  duplicated.  Place 
them  in  chase,  with  wooden  furniture  at  one  end  and  one  side, 
next  to  the  chase.  Place  inverted  brass  rules  around  each 
block  and  a  pica  slug  between  the  rules  which  are  at  the  ends 
of  the  block  where  they  meet  in  the  middle.  Lock  up  with 
Hempel  quoins  at  one  side  and  one  end.  Only  one  rule  is 
necessary  between  the  blocks  the  long  way.  The  brass  rules 
should  have  teats  or  lugs  soldered  on  to  catch  the  plates  at 
the  bevel  to  prevent  them  from  lifting  when  wax  mold  is 
being  lifted. 

BRASSPLATING  HALF-TONES.— Plating  with  brass 
is  not  an  easy  proposition  for  an  amateur  and  is  rendered 
unnecessarily  difficult  by  the  complicated  solutions  recom- 
mended by  most  writers.  The  following  formula  is  simple  and 
less  troublesome  to  keep  in  order  than  those  generally  advo- 
cated: i6  ounces  cyanid  of  potassium,  5  ounces  carbonate  of 
copper,  iJ/2  ounces  carbonate  of  zinc,  i  ounce  ammonia  and  i 
gallon  of  water.  The  deposition  of  brass  is  usually  attended 
with  some  difficulty  because  it  is  composed  of  two  metals,  one 
of  which  is  positive  and  the  other  negative ;  hence  the  current 
strength  requires  more  or  less  regulation  to  insure  uniform 
deposition  of  both  metals.  As  brass  contains  a  larger  pro- 
portion of  copper  than  of  zinc,  the  copper  in  the  bath  becomes 
first  exhausted,  and  sufficient  carbonate  of  copper  must  be 
added  to  restore  the  proper  proportions.  Cyanid  of  potassium 
must  be  supplied  when  the  action  of  the  bath  becomes  slug- 
gish. A  strong  current  is  required.  Constant  watchfulness  is 
necessary  to  keep  the  bath  in  good  working  condition.  To 
increase  the  wearing  qualities  of  zinc  half-tones,  the  "  Process 
Photogram"  suggests  facing  the  half-tone  with  brass,  and 
recommends  the  following  bath  formula :  Zinc  carbonate,  lo 
parts ;  copper  carbonate,  lo  parts ;  soda  carbonate,  20  parts ; 
soda  bisulphite,  20  parts ;  potassium  cyanid,  20  parts ;  arsen- 
ious  acid,  1-5  part;  water,  1,000  parts.  To  make  up  the  solu- 
tion, proceed  as  follows :     Take  12  parts  sulphate  of  copper 


ELECTROTYPINC;.  171 

and  12  parts  sulphate  of  zinc,  and  dissolve  them  in  water; 
then  add  carbonate  of  soda,  already  dissolved,  to  the  solution. 
This  precipitates  the  copper  and  zinc  in  the  form  of  carbonates, 
a  greenish-colored  powder.  Allow  the  precipitate  to  settle  and 
pour  off  the  supernatant  liquor.  Wash  the  precipitate  and 
then  mix  in  with  the  carbonate  and  bisulphite  of  soda  in  900 
parts  water.  Next  dissolve  the  cyanid  and  arsenic  in  the 
remaining  100  parts  of  water  and  pour  this  into  the  first  solu- 
tion.   This  bath  should  be  used  cold. 

BRITTLE  DEPOSIT. —  A  weak  current  always  and  under 
all  conditions  causes  the  deposition  of  a  harder  and  more 
brittle  nickel  than  a  current  of  medium  strength. 

BRONZING  SOLUTION.—  One  gallon  of  water,  Yi  ounce 
sulphate  of  potash,  ^  pint  of  ammonia.  This  mixture  should 
be  well  heated.  After  the  electrotype  has  been  immersed,  take 
it  out  and  apply  a  wet  scratch  brush  until  the  surface  assumes 
a  dark  cherry  hue,  which  is  a  favorite  color  with  art  lovers.  A 
very  beautiful  bronze  color  may  be  imparted  to  copper  arti- 
cles, such  as  medals  for  instance,  by  boiling  them  in  a  solution 
composed  of  verdigris,  S  ounces ;  muriate  of  ammonia,  5 
ounces ;  strong  vinegar,  ^/^  ounce.  Mix  the  verdigris  and  the 
sal  ammoniac  by  pulverizing  in  a  mortar  and  then  add  a  suf- 
ficient quantity  of  vinegar  to  form  a  paste.  Now  pour  this 
into  a  copper  vessel  with  a  pint  of  water  and  boil  for  about 
half  an  hour.  When  cold,  stand  the  mixture  aside  until  the 
sediment  has  subsided,  when  the  clear  liquor  may  be  poured 
off  and  bottled  until  required.  The  articles  to  be  bronzed 
should  be  boiled  in  this  liquor  for  ten  minutes  or  longer,  tak- 
ing care  that  they  do  not  come  in  contact  during  the  opera- 
tion. The  fumes  of  hydrochloric  acid  or  of  chlorid  of  lime 
will  produce  a  very  good  green  bronze  upon  electrotypes,  giv- 
ing them  the  appearance  of  ancient  bronze.  The  following 
process  is  recommended  by  Watt :  "  Electrotypes  may  be 
bronzed  by  suspending  them  in  a  wide-mouthed  bottle  (or 
other  vessel)  at  the  bottom  of  which  a  small  quantity  of  sul- 
phid  of  ammonium  has  been  placed.  The  sulphid  of  hydrogen 
which  escapes  will  give  a  good  bronze  tint  to  the  copper  in  a 


172  ELECTROTYPING. 

few  moments,  the  depth  of  tone  being  regulated  by  the  time 
of  exposure." 

BURNING. —  An  error  is  frequently  committed  in  nickeling 
with  too  strong  a  current,  the  consequence  being  that  the 
deposit  on  the  lower  portions  of  the  objects  soon  becomes  dull 
and  gray-black,  while  the  upper  portions  are  not  sufficiently 
nickeled.  This  phenomenon,  which  is  due  to  the  reduction  of 
the  nickel  with  a  coarse  grain  in  consequence  of  a  too  powerful 
current,  is  called  burning  or  overnickeling.  A  further  conse- 
quence of  nickeling  with  too  strong  a  current  is  that  the 
deposit  readily  peels  off  after  it  reaches  a  certain  thickness. 
This  phenomenon  is  due  to  the  hydrogen  being  condensed  and 
retained  by  the  deposit,  which  prevents  thick  deposition. 

CASES. —  Cases  made  of  electrotype  metal,  cast  in  the 
backing  pan  and  shaved  down  to  about  three-sixteenths  of  an 
inch  in  thickness,  are  superior  in  every  respect  to  the  expen- 
sive brass  pans  sold  by  manufacturers  of  electrotyping  machin- 
ery. The  soft  metal  may  be  easily  kept  in  shape  by  planing 
down  with  a  block  of  wood  after  each  use. 

CASES,  WARMING  OF.—  Warming  cases  by  laying  them 
on  the  steam  table,  although  quite  generally  practiced,  is  not  a 
good  plan,  for  it  softens  the  wax  next  the  case  more  than  on 
the  surface,  and  often  results  in  concaved  work.  Cases  should 
always  be  kept  in  a  "  hot  box,"  the  temperature  of  which 
should  be  so  regulated  as  to  keep  the  cases  in  proper  condition 
for  molding  without  additional  warming. 

CASTING  HARD  SHELLS.— It  will  be  found  that  there 
is  a  great  deal  of  difference  in  copper  shells  about  the  solder 
flowing  readily.  When  a  shell  is  extra  hard  the  solder  is 
invariably  obstinate  about  flowing. 

CATHODE. —  Cathode  is  the  pole  or  plate  by  which  an 
electric  current  leaves  a  depositing  solution.  In  electrotyping, 
the  wax  or  composition  mold  which  receives  the  deposit  of 
copper.    It  is  suspended  from  the  negative  pole  of  the  dynamo. 

CIRCUIT. —  A  circuit  is  the  entire  path  of  an  electric  cur- 
rent 


ELECTROTYPING.  173 

CLEANING  BRUSHES,  HALF-TONE.— Mr.  E.  R. 
Rodd,  superintendent  of  the  electrotyping  department  of  the 
Butterick  Publishing  Company,  is  the  inventor  of  certain  half- 
tone brushes  which  are  rapidly  becoming  popular  with  electro- 
type molders.  Although  these  brushes  are  made  of  metal,  the 
material  is  such  that  they  may  safely  be  applied  to  the  most 
delicate  half-tone  without  fear  of  injury.  By  the  aid  of  these 
brushes,  dirty  half-tones  may  be  thoroughly  cleaned  and  all 
the  original  detail  restored.  Two  brushes  are  employed.  The 
ink  or  dirt  in  the  half-tone  is  first  softened  with  wood  alcohol 
and  then  brushed  out  with  the  No.  i  brush.  The  cut  is  then 
covered  with  a  soft  rag  and  patted  gently  with  the  hand. 
After  the  cut  is  dry  it  is  rubbed  gently  with  the  No.  2  brush, 
and  again  after  the  form  has  been  blackleaded  until  all  the 
black  lead  has  been  removed. 

CLEANING  CUTS. —  The  molder  will  often  receive  forms 
containing  dirty  woodcuts,  though  not  so  many  now  as  for- 
merly, since  the  zinc  line  cuts  and  half-tones  have  to  such  an 
extent  taken  the  place  of  the  woodcut,  but  it  will  be  well  to 
know  a  liquid  that  will  clean  the  woodcut  nicely  and  which 
may  be  made  as  follows :  To  i  quart  of  alcohol,  add  J/2  ounce 
of  bisulphid  of  carbon  and  lYz  ounces  of  strong  liquid  ammo- 
nia; thoroughly  mix  and  apply  with  a  brush  as  you  would 
bezin.  This  wash  will  be  found  efficient  in  removing  ink  from 
a  woodcut,  or,  in  fact,  from  a  half-tone.  A  good  cleansing 
fluid,  according  to  Dunton,  is  composed  of  alcohol,  16  ounces ; 
carbon  disulphid,  i  ounce,  and  strong  fluid  ammonia,  2  ounces. 
This  may  be  used  in  the  same  way  as  benzin  and  will  be  found 
very  effectual. 

CLEANING  ELECTROTYPE  CASTS.—  Scrub  the  casts 
while  hot  with  kerosene  oil  and  powdered  pumice  stone.  Then 
lay  the  cast  in  a  shallow  sink  with  inclined  bottom,  and  steam 
it  out,  using  a  steam  hose  without  a  nozzle.  Then  take  the 
cast  to  a  sawdust  box  and  brush  it  thoroughly  with  clean,  dry 
sawdust  or  lay  it  on  a  heated  steam-table  until  dry. 

CLEANING  MACHINE,  PLATE.— The  Raisbeck  Elec- 
trotype Company,  of  New  York,  has  devised  a  machine  for 


174  ELECTROTYPING. 

cleaning  electrotype  plates,  which  is  said  to  be  superior  to  hand 
scouring  and  much  more  rapid.  The  machine  "  subjects  the 
face  of  the  plate  to  a  current  of  benzin  or  other  solvent  or 
detergent  simultaneously  with  gentle  friction.  We  accom- 
plish this  by  an  apparatus  which  moves  the  plate  to  be  cleaned 
backward  and  forward  several  times  in  contact  with  a  moving 
brush  of  the  proper  soft  material,  adjusted  sufficiently  near  to 
act  in  all  the  interstices.  In  the  most  complete  form  of  the 
invention  the  brush  is  caused  to  reverse  its  motion  on  the 
plate  and  thereby  to  act  more  effectively  in  the  recesses."  The 
apparatus  is  the  subject  of  letters  patent  No.  621,539. 

BLACK  ELECTROTYPES.— Seven  pennyweights  sul- 
phate of  barium,  i  quart  of  water.  After  the  article  has  been 
immersed  in  the  solution  a  light  brown  color  is  produced, 
which  gradually  deepens  until  it  assumes  an  intense  black.  The 
object  must  be  rinsed  in  hot  water  and  then  allowed  to  dry. 
To  secure  a  brilliant  polish,  all  that  is  necessary  to  do  is  to 
rub  it  with  chamois. 

COLOR-PLATES,  REGISTERING.— Fasten  the  plates 
to  the  blocks  by  driving  the  nails  only  part  way  in.  Then  draw 
your  nails,  cut  out  the  portions  of  the  plates  not  wanted,  and 
reblock  the  electros,  using  the  same  tack  holes.  This  will 
insure  a  perfect  register,  provided  your  blocks  have  first  been 
accurately  finished  to  the  same  size. 

COLORING  ELECTROTYPE  MEDALLIONS.— A  very 
pleasing  effect  may  be  produced  thus:  Having  well  cleaned 
the  electrotype,  apply  varnish  with  a  soft  brush  to  the  base 
or  flat  surface,  carefully  avoiding  the  figure ;  when  the  varnish 
has  become  hard,  attach  a  wire  to  the  electrotype  and  place 
it  in  a  gold  or  silver^  bath  for  a  short  time  until  sufficiently 
coated.  Now  remove  the  varnish  and  apply  the  bronzing 
material  to  the  copper  surface,  and  thus  the  figure  will  stand 
out  in  relief,  cither  in  gold  or  silver  as  the  case  may  be. 

CONCAVE. —  This  is  almost  invariably  caused  by  over- 
heating the  backs  of  the  cases,  which  softens  the  wax  next 
the  case  more  than  on  the  surface.  •  The  temperature  should 


ELECTROTYPING.  175 

be  uniform  throughout.  For  this  reason  it  is  advisable  to 
employ  a  "hot  box,"  i.  e.,  a  box  or  cabinet  heated  by  steam 
or  gas  and  so  arranged  that  the  cases  may  be  kept  at  just  the 
right  temperature  for  molding. 

CONDUCTIVITY  OF  LIQUIDS.— The  following  is  a 
list  of  the  conductivity  of  a  few  liquids  as  compared  with  that 
of  pure  silver : 

Pure    Silver    100,000,000,000 

Nitrate  of  copper,  saturated  solution 8,990 

Sulphate  of  copper,   saturated  solution 5,420 

Chlorid  of  sodium,   saturated  solution 31,520 

Sulphate  of  zinc,  saturated  solution 5,77o 

Sulphuric  acid,   i.io  specific  gravity 99,070 

Sulphuric  acid,   1.24  specific  gravity 132,750 

Sulphuric  acid,  1.40  specific  gravity 90,750 

Nitric  acid,  commercial 88,680 

Distilled  water  7 

CONDUCTIVITY,  INCREASING.— To  increase  the 
conductivity  of  a  blackleaded  wax  mold,  it  is  customary  to 
precipitate  a  film  of  copper  on  its  surface  by  the  well-known 
method  of  first  floating  the  mold  with  a  solution  of  sulphate 
of  copper  and  then  sprinkling  iron  filings  thereon.  Another 
method  consists  in  immersing  the  mold  for  a  few  moments 
in  a  solution  of  wood  alcohol  and  phosphorus,  afterward  par- 
tially drying,  then  rinsing  in  running  water  and  immediately 
suspending  in  the  bath.  This  method  is  specially  desirable  for 
nickeltyping.  The  phosphorus  solution  is  made  by  placing  a 
few  small  pieces  of  phosphorus  in  a  bath  of  wood  alcohol  and 
allowing  it  to  stand  for  three  or  four  days.  Phosphorus  is 
only  soluble  in  alcohol,  and  the  portion  dissolved  will  be  hardly 
perceptible,  but  will  be  sufficient  for  the  purpose.  While  phos- 
phorus is  a  dangerous  substance  to  handle,  on  account  of  its 
inflammability  when  exposed  to  the  air,  it  is  perfectly  safe 
if  kept  under  water  or  alcohol,  and  the  quantity  employed  is  so 
very  minute  that  no  danger  whatever  need  be  apprehended 
from  its  use  in  the  manner  described. 

CONNECTIONS,  GOOD.— It  has  been  frequently  noted 
that  electrotypers  do  not  always  appreciate  the  importance  of 
making  good  connections.  It  is  of  no  avail  to  provide  large 
conducting  rods  and  cross  rods  if  the  conducting  capacity  of 


176  ELECTROTYPING. 

the  rods  is  to  be  choked  off  at  the  points  of  contact,  which  is 
what  occurs  when  one  round  rod  is  laid  across  another  round 
rod.  It  is  obvious  that  unless  one  or  both  of  the  rods  is  flat- 
tened where  they  come  in  contact,  the  area  of  the  contact  will 
be  extremely  limited  compared  with  the  area  of  the  conductors 
on  both  sides  of  the  contact. 

COPPER  DISSOLVED  BY  SOLUTION.— An  electric 
current  passing  through  a  solution  of  sulphate  of  copper  will 
dissolve  copper  suspended  in  the  solution,  whether  it  is  in  the 
circuit  or  not.  This  fact  may  be  readily  tested  by  weighing 
a  small  piece  of  copper  and  hanging  it  in  the  solution,  without 
electric  connection,  and  after  a  few  hours  weighing  it  again. 
It  is  because  of  this  fact  that  extra  anodes  not  in  use,  if  left 
in  the  solution,  will  make  it  dense  and  heavy  at  the  bottom 
and  frequently  cause  the  deposit  to  be  spongy  and  granular. 

COPPER  SCRAPS  UTILIZED.— Copper  clippings  and 
scraps  may  be  utilized  as  an  anode  by  packing  them  in  a  per- 
forated lead  box  and  suspending  the  box  from  an  anode  rod. 
The  box  may  be  constructed  of  plates  of  electrotype  metal 
joined  at  the  corners  by  soldering.  It  should  be  somewhat 
longer  and  deeper  than  your  cases  and  about  four  inches  wide. 
The  perforations  should  be  as  near  together  as  possible. 

COPPER,  TO  SEPARATE  FROM  WATER.— There  is 
a  method  called  the  "  Cementation  Process,"  which  was 
employed  a  great  many  years,  "  for  separating  copper  from  the 
drainage  water  from  mines  containing  copper  in  solution 
derived  from  the  oxidation  of  mineral  sulphids  in  the  earth." 
By  this  process  the  water  is  brought  into  contact  with  scrap 
iron  and  its  copper  deposited  by  simple  immersion.  Under 
such  circumstances  the  copper  separates  in  little  loose  crystals 
termed  "  cementation  copper,"  which  contains  nearly  all  the 
impurities  of  the  iron  u.sed  to  precipitate  it,  and  requires  to 
be  purified.  Spain  and  Portugal  export  about  half  a  million 
tons  annually  of  iron  pyrites  containing  several  per  cent  of 
copper,  the  whole  of  which  is  extracted  by  this  process. 


ELECTROTYPING.  177 

COPPER,  WEIGHT  OF.—  A  copper  shell  .005  of  an  inch 
thick  weighs  about  3.71  ounces  per  square  foot.  One  cubic 
inch  of  copper  weighs  5.1585  ounces. 

CORROSION  OF  COPPER-FACED  TYPE.— In  a  dry 
atmosphere  and  under  ordinary  conditions,  copper  will  not 
corrode  to  an  extent  sufficient  to  injure  printing-plates,  or 
type  faced  with  copper,  but  there  are  certain  colored  inks 
which  attack  copper  by  reason  of  the  mercury  contained  in 
them,  and  certain  cleaning  compounds  containing  ammonia 
which  would  be  likely  to  produce  corrosion  if  allowed  to 
remain  on  the  type.  Verdigris  may  be  removed  from  copper 
by  brushing  with  very  dilute  nitric  acid  or  ammonia  and  thor- 
oughly rinsing  with  clear  water. 

CORROSION,  TO  PREVENT.— Copper  soon  loses  its 
luster  when  exposed  to  the  atmosphere,  but  the  printing  quality 
of  the  electrotype  is  not  impaired  thereby.  When  electrotypes 
are  stored  in  a  d^mp  vault  or  exposed  to  the  action  of  acid 
fumes  or  gases  which  cause  excessive  corrosion,  damage  will 
of  course  result.  The  remedy  is  to  remove  the  plates  to  a 
dry  place.  If  such  a  place  is  not  available,  a  coat  of  hot 
paraffin  will  protect  them  to  some  extent,  or  they  may  be 
given  a  coat  of  lacquer  such  as  is  used  to  preserve  the  luster 
on  certain  kinds  of  metal  artwork.  Most  electrotypers  would 
ridicule  the  idea  of  spending  any  time  or  money  in  an  attempt 
to  preserve  the  color  of  an  electrotype,  and  if  they  are  care- 
fully cleaned  and  stored  in  a  dry  place  there  is  really  no 
necessity  for  further  protection. 

COST  OF  ELECTROTYPE  SHELLS.— The  material  in 
a  tinned  shell  costs  about  .05  of  a  cent  per  square  inch.  The 
cost  of  molding  and  the  various  other  operations  involved  in 
producing  a  shell  are  estimated  to  be  about  one-half  the  cost 
of  the  finished  electrotype.  It  is  customary,  therefore,  to 
charge  half  price  for  shells.  From  the  seller's  standpoint  this 
is  a  satisfactory  method  of  estimating,  but  as  a  matter  of  fact 
the  cost  of  the  shells  is  considerably  less  than  one-half  the 
cost  of  finislicd  book-plates.  That  is  to  say,  the  value  of  the 
metal  in  the  plates,  together  with  the  labor  of  backing  up  and 

12 


178  ELECTROTYPJNG. 

finishing,  is  actually  about  two-thirds  of  the  total  cost  cf  the 
electrotypes. 

COULOMB. —  A  coulomb  is  the  amount  of  current  which 
passes  through  a  conductor  in  one  second  when  the  strength 
of  current  is  one  ampere. 

CROCUS. —  Crocus  is  sometimes  used  to  prevent  the  form 
from  "  sliding "  and  also  to  prevent  the  wax  from  sticking 
to  solid  cuts  and  causing  them  to  be  rough.  If  used  at  all, 
it  should  be  carefully  brushed  off  the  mold  before  it  goes  into 
the  vat,  otherwise  it  is  a  frequent  cause  of  "  blisters "  and 
"  sinks." 

CURRENT,  HIGH  TENSION.— The  incandescent  light 
current  will  not  answer  for  electrotyping  or  plating,  because 
the  tension  is  too  high.  The  voltage  of  an  electric  light  machine 
is  no  or  more,  while  one  to  three  volts  is  amply  sufficient  for 
electrotyping.  There  are  other  reasons,  not  necessary  to 
explain,  why  the  electric  light  current  would  be  unsuitable  for 
electrotyping. 

CURRENT  STRENGTH.—  Current  strength  is  the  quan- 
tity of  electricity  which  flows  through  any  cross  section  of  a 
circuit  in  one  second  of  time;  it  depends  on  the  electromotive 
force  and  the*  total  resistance.  The  unit  of  measurement  is 
called  ampere  (see  Ampere).  According  to  Ohm's  law,  the 
strength  of  current  is  equal  to  electromotive  force  divided  by 
resistance.  Current  strength  is  measured  by  means  of  an 
ammeter. 

CURRENTS,  MEASURING  ELECTRIC— The  ammeter 
is  employed  to  measure  electric  currents,  and  the  voltmeter,  to 
measure  the  electromotive  force  or  pressure.  Speaking  of 
water  flowing  through  a  pipe,  we  would  say  that  it  is  delivered 
at  the  rate  of  so  many  gallons  per  minute.  The  quantity  would 
depend  upon  the  pressure  behind  it  and  the  friction  of  the 
pipe.  So  with  the  electric  current ;  the  number  of  amperes 
delivered  depends  on  the  pressure  (E.  M.  F.)  and  the  resist- 
ance of  the  conductors.  If  the  pressure  is  one  volt  and  the 
resistance  one  ohm,  the  current  delivered  will  be  one  ampere 


ELECTROTYl'lNG.  179 

per  second.  If  the  resistance  is  only  .01  of  an  ohm,  the  cur- 
rent will  be  100  amperes  per  second.  The  current  always 
equals  the  E.  M.  F.  divided  by  the  resistance.  Inasmuch  as 
the  current  depends  on  the  resistance  as  well  as  the  pressure, 
it  is  obvious  that  the  voltmeter  will  not  always  accurately 
measure  the  current,  for,  while  one  volt  pressure  may  produce 
100  amperes  under  certain  conditions  of  resistance,  under 
different  conditions  the  product  may  be  more  or  less  than  100 
amperes ;  and,  while  one  volt  may  produce  100  amperes,  it 
does  not  always  follow  that  two  volts  will  produce  200  amperes, 
for  increasing  the  pressure  may  increase  the  resistance  by 
heating  or  polarization.  A  current  of  one  ampere  will  deposit 
18. 1 16  grains  of  copper  per  hour,  and  as  the  ammeter  is 
employed  to  measure  the  current  after  resistance  has  been 
overcome,  its  working  value  is  always  uniform.  On  the  other 
hand,  a  current  of  one  volt  E.  M.  F.  may  deposit  more  or  less 
copper  at  different  times  as  the  conditions  of  resistance  vary. 
It  is,  therefore,  evident  that  the  true  working  value  of  the 
current  can  be  measured  only  by  the  ammeter  and  can  not  be 
accurately  measured  by  the  voltmeter. 

CURVED  ELECTROTYPES,  CASTING.— Many  of  the 
pages  (all  of  the  colorwork)  of  the  Chicago  Blade  and 
Chicago  Ledger  are  printed  from  curved  electrotype  plates 
which  are  cast  by  pouring  the  stereo  metal  directly  into  the 
tinned  shell,  in  the  same  manner  that  a  stereotype  plate  is 
cast  from  a  paper  matrix. 

CURVED  PLATES,  EXPANSION  OF.— The  only  way 
to  prevent  expansion  in  curved  plates  is  to  curve  the  shell  and 
cast  it  in  a  curved  box.  Most  electrotypers  consider  this  an 
impractical  method,  although  the  writer  knows  of  one  large 
publication  whose  color  pages  are  all  printed  from  plates  made 
in  this  manner.  While  it  is  obviously  impossible  to  curve  an 
electrotype  without  stretching  it,  the  expansion  may  be  mini- 
mized by  surrounding  the  form  with  wide  bearers  and  cutting 
down  spaces  so  as  to  niake  the  plate  as  nearly  solid  as  possible. 
A  form  of  open  type  matter  will  always  stretch  more  than  a 
solid  tint  or  half-tone. 


180  ELECTROTYPING 

DEPOSITION,  ECONOMICAL.— It  is  a  waste  oi  power 
to  run  the  dynamo  at  a  high  voUage  and  prevent  "  burning " 
by  cutting  down  the  conductivity  of  the  solution  or  increasing 
its  resistance.  It  would  obviously  be  in  the  interest  of  economy 
to  make  the  solution  as  conductive  as  possible  and  adapt  the 
current  strength  to  the  solution. 

DEPOSITION,  RATE  OF.— One  ampere  deposits  18.116 
grains  of  copper  per  hour;  10  amperes  deposit  9.84  ounces  in 
24  hours ;  386.4  ampSres  deposit  i  pound  in  i  hour ;  746 
amperes  deposit  1.93  pounds  of  copper  in  i  hour;  17.94 
amperes  per  square  foot  deposit  .001  inch  thickness  of  copper 
per  hour. 

DURABILITY  OF  ELECTROTYPE  PLATES.— Accord- 
ing to  the  New  York  Times,  the  greatest  achievement  in 
connection  with  the  printing  of  "  David  Harum  "  was  the  part 
played  by  the  plates  from  which  the  book  was  printed.  Only 
one  set  has  been  used  to  print  425,000  copies.  When  certain 
signs  indicated  that  "  David  Harum "  was  fast  winning  an 
extraordinary  popularity,  a  second  set  of  electrotype  plates 
was  made,  to  be  used  in  case  of  emergency,  but  so  well  has 
the  electrotyper  done  his  work  that  this  set  has  not  as  yet 
been  pressed  into  service. 

DYNAMO,  CHOOSING  A.— When  making  choice  of  a 
dynamo,  it  should  be  remembered  that  a  certain  volume  of 
current  is  required  to  produce  certain  results.  According  to 
Gore,  17.94  amperes  will  deposit  .001  of  an  inch  thickness  per 
hour  on  a  square  foot  of  cathode.  A  dynamo  whose  capacity 
is  360  amperes,  or  twenty  times  17.94,  will,  therefore,  deposit  20 
square  feet  at  a  time  at  the  rate  of  .001  of  an  inch  per  hour, 
or,  to  put  it  in  another  way,  it  will  deposit  6,480  grains  of 
copper  per  hour.  By  increasing  the  E.  M.  F.  of  the  dynamo 
this  weight  of  copper  may  be  deposited  .002  of  an  inch  thick 
on  10  square  feet  of  copper,  or  .004  of  an  inch  thick  on  5 
square  feet,  or  even  .008  of  an  inch  thick  on  2J/S  square  feet, 
but  the  limit  of  the  capacity  of  the  dynamo  in  weight  of 
copper  deposited  per  hour  is  6,480  grains,  and  this  limit  can 
not  be  exceeded.     It  is  obvious,  therefore,  that  to  perform  a 


ELECTROTYPING.  181 

large  amount  of  work  in  a  limited  time  requires  a  large 
dynamo.  The  best  results  which  the  writer  has  ever  seen 
produced  in  an  electrotype  foundry  were  obtained  from  a 
lo-volt,  i,ooo'-ampere  dynamo  coupled  to  three  baths  in  series, 
and  arranged  in  such  a  way  that  one  of  the  baths  may  be 
disconnected  when  it  is  desired  to  hurry  the  work  in  the  other 
two.  Ordinarily  the  E.  M.  F.  is  sYs  volts  per  bath  and  the 
time  required  to  deposit  a  satisfactory  shell  is  from  forty-five 
to  sixty  minutes,  but  this  time  may  be  reduced  to  thirty  minutes 
or  less  by  utilizing  the  entire  pressure  in  two  vats.  This 
machine  will  deposit  thirty  feet  of  good  shells  per  hour  or 
about  one  hundred  pounds  of  copper  per  day,  and  will  take 
care  of  the  product  of  four  molding  presses. 

ELECTROMOTIVE  FORCE.— The  electromotive  force 
of  a  current  means  that  power  by  virtue  of  which  it  can  sur- 
mount resistance.  A  current  of  low  electromotive  force  may 
be  entirely  stopped  or  absorbed  by  a  moderate  resistance.  A 
current  of  high  electromotive  force  can  overcome  a  high 
resistance  or  accomplish  work  in  such  a  circuit. 

ELECTROTYPES,  NEW  METHOD  OF  MAKING.— 
A  sheet  of  thin  metal,  copper  or  an  alloy  of  copper  and  some 
other  metal,  is  laid  on  the  type-form,  which  is  then  covered 
with  a  blanket  and  passed  through  a  machine  similar  to  a 
matrix-rolling  machine.  The  blanket  is  then  removed  and  a 
sheet  of  softened  gutta-percha  substituted  therefor,  after  which 
the  form  is  passed  through  the  machine  again.  This  gives  a 
deep  and  sharp  impression  of  the  type  in  the  sheet  metal,  which 
is  now  stripped  from  the  form  and  backed  up  with  electrotype 
metal.  It  is  claimed  that  the  plates  obtained  by  this  process 
are  satisfactory  except  possibly  in  the  case  of  very  fine-screen 
half-tones. 

ELECTROTYPING  IN  AMERICA.— According  to  the 
"  Typothetae  and  Platemaker,"  there  are  372  firms  in  the 
United  States  and  Canada  who  make  electrotyping  their  sole 
business,  and  New  York  city  has  about  ten  per  cent  of  them. 

FINISHING  HALF-TONES.— If  half-tone  shells  are 
made   extra   heavy,    there   will   be   no   necessity   for    using   a 


182  ELECTROTYPING. 

smasher  in  finishing  the  plate ;  in  fact,  little  or  no  finishing 
should  be  required  other  than  straightening.  If  punching  is 
unavoidable,  it  is  a  good  plan  to  employ  a  sheet  of  soft  paper 
to  protect  the  face  of  the  plate. 

FINISHING  VIGNETTED  HALF-TONES.— Before 
straightening  the  electro,  take  a  punch  of  suitable  shape  and 
go  around  just  outside  the  edge  of  the  vignetting.  This  will 
have  the  effect  of  sinking  the  edge  a  little  below  the  level. 
When  straightening  the  plate  do  not  bring  up  the  edges  of 
the  vignetting,  but  leave  it  a  little  lower  than  the  half-tone. 
The  result  will  be  that  the  print  will  shade  off  to  nothing 
and  give  the  soft  effect  of  the  original. 

FOREMAN'S  SALARY,  THE.— There  is  a  vast  differ- 
ence in  foremen,  just  as  there  is  among  workmen.  The  ideal 
foreman  possesses  large  executive  ability,  has  a  thorough 
knowledge  of  his  business  and  has  his  employer's  interests 
always  at  heart.  He  keeps  his  machinery  in  first-class  work- 
ing order  and  is  as  careful  in  expenditures  as  if  the  business 
were  his  own.  He  secures  and  retains  the  respect  of  his  men 
and  obtains  from  them  their  best  efforts.  He  is  prompt,  accu- 
rate, energetic  and  courteous,  and  always  a  hustler.  There 
are  only  a  few  of  him.  His  services  are  in  demand  at  good 
wages,  and  he  is  worth  more  than  he  gets. 

GUTTA-PERCHA  MOLDS.— If  the  character  of  the 
work  is  such  that  black  lead  is  not  objectionable,  it  may  be 
used,  in  preparing  for  the  bath,  the  same  as  on  a  wax  mold. 
On  molds  of  half-tones  or  steel  engravings,  the  molds  may 
be  coated  with  silver.  The  following  is  an  extract  from  a  shop 
talk  by  Mr.  G.  J.  Kelly,  of  London,  England :  "  Gutta-percha 
is  a  product  of  the  earth,  and,  in  its  natural  state,  is  of  a  white 
color ;  it  is  gritty  usually,  and  wants  careful  washing  before 
manipulating.  There  are  three  kinds  of  gutta-percha  in  the 
market ;  the  purest  is  white,  the  next  brown,  and  the  last  or 
commercial  article  is  black.  The  third-class  article,  for  pur- 
poses in  the  trade,  is  the  best.  Of  course  there  are  various 
grades  of  black  percha,  and  the  choice  is  a  difficult  matter, 
known  best  to  those  who  have  had  to  try  inferior  material 


ELECTROTYPING.       .  183 

through  economizing.  The  pcrcha  should  be  about  one-eighth 
inch  in  thickness  and  carefully  rolled  out  in  sheet.  It  should 
be  hard  and  without  any  patches  of  '  brown '  in  its  composi- 
tion, because  a  good  percha  is  always  black  and  shiny  as 
ebony  after  pouring.  Now  the  next  thing  is  its  touch ;  it 
should  be  free  from  clamminess  and  dry  to  the  finger.  If 
there  is  a  tendency  to  stick,  you  may  reckon  at  once  that  the 
tar,  or  whatever  foreign  substance  it  contains,  means  trouble 
in  store.  When  you  have  chosen  your  percha,  it  will  suit 
your  purpose  best  to  cut  it  up  into  strips  and  then  into  squares 
of  about  four  inches.  It  will  not  run  down  as  wax  when 
steam  or  heat  is  applied,  and  here  begins  the  addition  of  fat. 
If  you  get  English  mutton  fat,  you  have  the  very  best  article 
for  mixing  with  gutta-percha.  We  now  have  selected  our  two 
principal  materials,  and  we  place  in  the  same  pan  say  four 
pounds  percha  and  one  pound  fat.  Then  mix  and  stir  the 
percha  and  fat  together  with  a  painter's  knife  say  ten  inches 
long.  You  mix  and  stir  for  some  time,  the  longer  the  better, 
because  all  the  air  must  be  exuded.  The  plate  to  be  duplicated 
must  be  absolutely  free  from  dirt.  The  temperature  of  the 
plate  should  be  hot  enough  to  enable  one  to  touch  the  plate 
with  the  fingers,  and  no  more.  You  plunge  the  knife  in  and 
then  take  a  portion  of  the  percha  on  the  blade  from  out  of  the 
pan,  and  pour  exactly  in  the  center  of  the  plate,  and  this  must 
be  done  to  prevent  airholes.  We  have  now  poured  a  mold, 
and  we  immediately  remove  the  same  from  the  heat  to  a  cold 
slab  for  cooling.  After  the  mold  has  set  and  cooled,  I  take  it, 
press  the  edge  of  the  mold  gently  down,  the  original  upward, 
and,  if  I  find  the  mold  loosen  from  the  corners,  I  gently  lift 
the  original  off  by  means  of  a  paring  knife.  If  I  find  the 
slightest  tendency  in  the  percha  to  cling  to  the  original,  I  give 
the  mold  another  half  hour.  You  may  find  that  the  mold 
may  never  come  off;  in  other  words,  it  will  stick  for  all  it  is 
worth.  Well,  that  is  caused  by  pouring  your  material  too  hot 
or  on  a  dirty  original.  If  your  mold  has  creases  or  airholes, 
it  is  cold  material,  and  all  this  can  be  overcome  only  by  expe- 
rience.    I  face  the  mold  by  pouring  and  drying  on  the  face  a 


184  ELECTROTYPING. 

solution  of  phosphorus  and  silver  nitrate,  which  immediately 
gives  it  sufficient  conductibility  to  cover  the  mold  by  an  ordi- 
nary Smee  battery  in  thirty  seconds." 

HALF-TONES  AND  ELECTROTYPES.—  Half-tone 
shells  should  be  made  extra  heavy,  so  that  the  pressure  or 
weight  of  the  metal  will  not  distort  them  or  force  to  the 
surface  those  portions  of  the  shell  corresponding  to  the  high 
lights  in  the  picture  and  which  are  a  trifle  low  in  the  engraving. 
The  same  caution  applies  to  the  vignette.  It  is  too  much  to 
expect  that  electros  will  be  absolutely  perfect.  There  is  prob- 
ably always  some  loss  in  reproduction,  notwithstanding  the 
claim  of  some  electrotypers  to  the  contrary.  Sometimes  the 
loss  is  hardly  perceptible,  but  an  expert  will  usually  detect  a 
difference. 

HALF-TONES  INSERTED  IN  ELECTROTYPE 
PLATES. —  The  method  most  commonly  employed  is  to  back 
up  the  etching  to  the  thickness  of  the  book-plate,  then  fit  it 
into  the  plate  and  secure  it  by  soldering.  Mr.  P.  M.  Furlong's 
process,  which  is  patented,  is  described  as  follows :  A  base 
or  blank  block  is  fitted  under  the  etching  to  make  it  type-high, 
and,  having  been  properly  trimmed  to  fit  into  the  type-form, 
the  etching  is  removed  and  the  base  alone  is  locked  up  in  the 
form  with  the  type.  The  removal  of  the  etching  is  necessary 
in  order  that  the  type  may  be  blackleaded  to  cause  it  to  freely 
release  from  the  molding  composition  in  the  operation  of  mold- 
ing, and  it  being  preferable  that  the  face  of  the  etching  should 
not  be  blackleaded.  After  blackleading  the  type-form,  the 
etching,  having  had  its  back  thoroughly  cleaned,  is  replaced 
face  upward  on  the  base  within  the  form,  with  its  face  flush 
with  the  type,  and  then  the  surface  of  the  molding  composi- 
tion having  been  coated  with  plumbago,  the  form  is  molded 
in  the  usual  way.  When  the  mold  thus  obtained  is  lifted  from 
the  form,  the  etching  will  be  found  imbedded  in  and  adhering 
to  the  molding  composition,  face  inward.  The  mold  contain- 
ing the  etching  is  then  blackleaded  in  the  usual  way  prepara- 
tory to  being  placed  in  the  electrotyping  bath ;  but,  before 
being  placed  in  the  bath,  the  exposed  back  of  the  etching 


ELECTROTYPING.  185 

should  be  freed  from  black  lead  and  scraped  bright  to  insure 
the  incorporation  of  the  electro-deposited  metal  with  the  back 
and  edges  of  the  etching  and  in  order  that  the  metal  may  be 
deposited  in  a  continuous  and  unbroken  sheet  over  the  edges 
of  the  etching  to  the  back  thereof  and  thereby  form  a  perfect 
union  between  the  electrotype  and  the  etching,  so  that  when 
the  shell  is  removed  from  the  mold  it  brings  the  etching  with 
it,  the  two  forming  practically  one  plate,  which,  after  having 
been  freed  from  adhering  wax  or  molding  composition,  may 
be  backed  with  composition  metal  and  finished  in  the  same 
manner  as  ordinary  electrotype  plates.  By  this  simple,  direct 
and  economical  process,  an  absolutely  perfect  incorporation  of 
an  etching  plate  with  an  electrotype  of  reading  matter  is 
obtained. 

HALF-TONES,  MOLDING.—  Molding  half-tones  requires 
considerable  skill  and  careful  attention  to  every  detail  of  the 
process.  The  molding  composition  must  be  of  a  certain  tem- 
perature, which  can  not  be  described  but  must  be  learned  by 
experience;  the  blackleading,  washing  and  coating  should  be 
performed  with  the  utmost  care,  to  avoid  filling  up  the  minute 
hatches  of  the  engraving;  and,  lastly,  you  should  not  attempt 
to  mold  half-tones  in  connection  with  type.  Mold  them  sepa- 
rately, and,  after  the  plates  are  finished,  insert  the  engraving  in 
the  page.  It  is  impossible  to  learn  electrotype  molding  from 
written  instructions.  Skill  comes  only  from  long  practice 
under  the  tutelage  of  an  expert  workman. 

HOLES  IN  SHELLS.—  Holes  in  the  shells  are  due  either 
to  defective  blackleading,  failure  to  remove  the  air  from  the 
mold  by  thorough  wetting  before  placing  in  the  bath,  or  the 
use  of  a  current  so  strong  that  it  causes  the  formation  of 
hydrogen  gas  on  the  cathode.  Defective  blackleading  may  be 
caused  by  a  poor  quality  of  graphite  or  insufficient  brushing. 
The  best  way  to  wet  the  surface  of  the  mold  is  to  place  it 
face  up  in  a  tank  partially  filled  with  water  in  such  a  man- 
ner that  the  mold  will  be  an  inch  or  two  under  the  surface, 
and  then  direct  a  stream  of  water  from  a  rotary  force  pump 
on  to  the  mold.     If  trouble  is  due  to  the  third  cause,  the 


186  ELECTROTYPING. 

remedy  is  to  reduce  the  speed  of  your  dynamo  or  use  an 
agitator.  The  latter  is  by  far  the  best  plan,  as  the  agitator 
will  not  only  dissipate  the  gas  bubbles  but  will  enable  you  to 
employ  a  current  twice  as  strong  as  would  be  practicable  with 
your  solution  test,  and  thus  double  the  rate  of  deposition. 

HORSE-POWER. —  One  horse-power  equals  746  watts. 
The  unit  of  electric  output:  1,000  watts  equals  1.34  horse- 
power; I  horse-power  equals  746  amperes  —  with  i-volt  pres- 
sure causes  1.93  pounds  of  copper  to  be  deposited  per  hour. 

HOT  BOX,  DUNTON'S.— The  cabinet  consists  of  two 
boxes,  one  built  inside  of  the  other  and  having  an  air  space 
between  them.  The  outer  box  should  be  constructed  of  heavy 
material,  or,  better  still,  of  two  thicknesses  of  board,  with  a 
lining  of  thick  asbestos  board  between  the  wooden  walls. 
This  keeps  all  the  heat  on  the  inside.  Both  boxes  should  be 
built  practically  tight;  that  is,  do  not  bore  any  holes  through 
the  walls  of  the  inner  box  to  communicate  with  the  heat  space 
between  the  boxes.  This  is  unnecessary  and  a  detriment  to 
the  satisfactory  working  of  the  cabinet.  The  radiating  space 
between  the  outer  and  inner  boxes  should  be  at  least  six 
inches;  that  is,  the  walls  of  the  inner  box  should  be  placed 
six  inches  from  those  of  the  outer,  on  the  top,  ends  and  sides, 
while  on  the  under  side  there  should  be  at  least  eight  inches, 
and  the  floor  of  the  inner  box  should  be  made  of  two  thick- 
nesses, with  a  layer  of  asbestos  paper  between  them.  The  heat- 
ing coils,  consisting  of  six  lengths  of  ^-inch  steam  pipe,  should 
run  lengthwise  of  the  cabinet  and  be  placed  under  the  floor 
or  bottom  of  the  inner  box.  There  should  be  at  least  six  inches 
between  the  top  of  the  pipes  and  the  floor  of  the  inner  box, 
and  they  should  be  supported  on  iron  rods  going  through  the 
walls  of  the  outer  box.  The  doors  and  their  casings  need  spe- 
cial attention ;  they  must  not  be  made  of  a  single  thickness 
of  wood,  for  this  might  spoil  the  satisfactory  working  of  the 
whole  affair.  They  should  be  constructed  of  two  thicknesses 
of  wood,  with  an  air  space  between,  similar  to  those  on  a 
refrigerator,  and  closed  in  on  the  sides,  top  and  bottom,  having 
holes  of  at  least  an  inch  in  diameter  bored  at  intervals  on  the 


ELECTROTYPING.  187 

four  sides,  corresponding  to  the  same  holes  bored  in  the  cas- 
ings, to  connect  the  air  spaces  with  the  heat  chamber  of  the 
cabinet.  Both  doors  should  be  provided  with  springs,  so  that 
they  will  not  be  left  open  after  molds  have  been  taken  out  of 
or  placed  in  the  cabinet.  The  volume  of  heat  can  be  regulated 
perfectly  satisfactory  by  the  manipulation  of  the  valve  in  the 
steam  pipe.  The  cabinet  should  stand  up  off  the  floor  at  least 
six  inches,  and  be  located  handy  to  the  wax  shaver  and  filling 
tables. 

INVENTIONS. —  It  is  gratifying  to  note  that  inventors 
are  taking  up  the  subject  of  electrotyping  and  striving  to 
produce  more  economical  or  more  convenient  methods  of 
manufacture.  The  invention  or  discovery  of  a  compound  to 
satisfactorily  anneal  ozokerite  may  be  mentioned  as  an  indica- 
tion of  what  may  be  expected  in  the  way  of  improvement.  A 
firm  of  Brooklyn  chemists  has  just  put  on  the  market  a  solder- 
ing fluid,  ready  for  use,  which  does  away  with  the  use  of 
muriatic  acid  and  the  disagreeable  and  unhealthy  process  of 
"  killing "  it  with  zinc.  Another  inventor  claims  to  have  dis- 
covered a  material  which  acts  as  a  precipitant  of  copper  to  be 
used  in  the  place  of  iron  filings,  thus  eliminating  all  danger  of 
scratching  the  molds.  The  electrotyping  business  is  suscepti- 
ble of  much  improvement. 

IRON  DEPOSITION  OF.— Deposition  of  iron,  except  for 
the  purpose  of  "  steel  facing,"  is  seldom  practiced  in  this 
country,  and  there  are  probably  not  half  a  dozen  establish- 
ments which  are  equipped  for  such  work.  In  St.  Petersburg, 
however,  M.  Klein  has  been  very  successful  in  producing  elec- 
trotypes in  iron,  which  are  largely,  if  not  exclusively,  employed 
in  the  printing  of  state  papers,  documents,  labels,  etc.  Some 
of  these  electrotypes,  which  were  on  exhibition  at  the  Colum- 
bian Exposition,  were  very  heavy  and  would  indicate  that  there 
is  no  limit  to  the  thickness  which  may  be  deposited  with  proper 
facilities. 

LEVELING  ELECTROTYPES.— In  a  recent  patented 
process  for  leveling  electrotypes,  the  method  consists  in  intro- 
ducing  the   backing   pan   and   its    contents   into   an   air-tight 


188  ELECTROTYPING. 

chamber  and  of  forcing  artificially  cooled  air  into  the  chamber 
at  a  high  pressure  in  order  to  cool  and  level  the  electrotype. 

LITMUS  PAPER. —  Blue  litmus  paper  is  colored  red  by 
acid  fluids,  and  red  litmus  paper  blue,  by  alkaline  fluids.  By 
simultaneously  dipping  one-half  a  strip  of  blue  and  of  red 
litmus  paper  in  a  solution,  the  reaction  of  the  fluid  can  be 
judged  from  the  change  in  color  and  the  rapidity  and  intensity 
of  its  appearance. 

MEASURING  INSTRUMENTS.—  Instruments  for  meas- 
uring electric  currents  should  be  included  in  the  equipment  of 
every  well-ordered  electrotyping  establishment.  In  the  early 
days  of  the  art,  it  was  sufficient  to  know  that  a  current  of  some 
kind  was  at  work  and  that  in  the  course  of  time  a  shell  of  the 
desired  thickness  would  be  deposited.  It  might  take  twelve 
hours  at  one  time  and  eighteen  at  another,  but  a  few  hours 
more  or  less  was  not  considered  of  serious  moment.  With 
the  modern  electrotyper,  however,  every  minute  counts,  and, 
as  a  rule,  he  employs  all  the  current  which  can  be  utilized 
without  "  burning  "  the  deposit.  Having  learned  by  experience 
what  quantity  may  be  employed  to  advantage,  it  is  of  great 
convenience  to  be  able  to  measure  the  current  and  by  means  of 
the  proper  registering  instruments  maintain  the  pressure  at 
the  maximum  point.  The  voltmeter  and  ammeter  are  also 
useful  indicators  of  the  condition  of  the  solution.  For  instance, 
with  the  solution  properly  proportioned  and  the  tanks  con- 
nected in  multiple,  a  pressure  of  2^^  volts  should  produce  a 
current  strength  of  about  seventy-five  amperes  per  square  foot 
of  cathode.  If  the  ammeter  registers  less,  it  is  an  indication 
that  the  solution  is  deficient  in  acid. 

METALS  USED  IN  ELECTROTYPING,  MELTING 
POINT  OF.— Antimony,  840°  F.;  copper,  1,196°  F.;  lead, 
617°  F.;   tin,  773°  F. 

METAL  ELECTROTYPE.— Electrotype  backing  metal 
is  composed  of  lead,  tin  and  antimony.  The  proportions  may 
vary  somewhat.  The  most  popular  formula  is :  Lead,  90 
pounds;    tin,  5  pounds,  and  antimony,  5  pounds.     However,  6 


ELECTROTYPING.  189 

pounds  of  tin  and  4  pounds  of  antimony,  or  6  pounds  of  anti- 
mony and  4  pounds  of  tin,  may  be  employed  with  good  results. 
Electrotype  metal  fuses  at  about  600°  F. 

METAL-POTS,  CAPACITY  OF.— To  calculate  the  con- 
tents of  a  round  pot,  multiply  the  cube  of  the  diameter  by  the 
decimal  .5236  and  divide  by  2,  to  find  the  number  of  cubic 
inches.  To  calculate  the  contents  of  a  square  pot  in  cubic 
inches,  multiply  the  length,  breadth  and  depth  together.  On 
account  of  the  slope  in  the  walls  of  the  pot,  the  length  and 
breadth  measurements  should  be  taken  at  a  point  equally 
distant  from  the  top  and  bottom  of  the  pot.  A  cubic  inch  of 
stereo  metal  weighs  6.15  ounces.  A  cubic  inch  of  electro  metal 
weighs  6.28  ounces. 

METALS  USED  IN  ELECTROTYPING,  SPECIFIC 
GRAVITY  OF.— Antimony,  6.70;  copper,  8.889;  lead,  8.01; 
tin,  T.z. 

MOLDING  COMPOSITION.— Most  molders  have  their 
own  opinion  as  to  what  constitutes  the  best  molding  composi- 
tion. Possibly  no  two  of  them  use  exactly  the  same  com- 
bination of  ingredients,  and  yet  all  produce  excellent  results. 
Some  of  the  best  molders  still  use  beeswax  and  decline  to 
accept  a  substitute ;  others  use  ozokerite ;  others  "  crask  " 
wax,  which  has  ozokerite  for  a  base ;  others  a  combination 
of  ozokerite  and  beeswax,  or  "  crask "  wax  and  beeswax. 
All  molding  compositions  are  subject  to  changes,  caused  by 
repeated  meltings  and  coolings,  changes  of  temperature,  etc. 
The  skilled  molder  watches  his  wax  and  adds  from  time  to 
time  the  material  necessary  to  preserve  its  virtue.  A  good 
molding  composition  may  be  made  by  mixing  together  pure 
beeswax,  85  per  cent ;  crude  turpentine,  10  per  cent ;  plum- 
bago, 5  per  cent.  In  summer  add  5  per  cent  burgundy  pitch. 
Ozokerite  may  be  substituted  for  beeswax  and  is  becoming 
popular  as  a  molding  composition.  The  following  mixture  is 
specially  recommended  by  Mr.  George  E.  Dunton :  10  pounds 
ozokerite,  Y^  pound  vaseline  and  %  to  y2  pounds  of  white- 
pine  pitcli.     If  by  long  use  the  composition  becomes  hardened. 


190  ELECTROTYPING. 

it  may  be  annealed  by  adding  from  time  to  time  a  small  quan- 
tity of  vaseline. 

MOLDING  COMPOSITION,  ELASTIC— Dissolve  32 
parts  (by  weight)  of  gelatin  in  24  parts  of  water,  over  a  slow 
fire ;  when  dissolved,  add  i  part  beeswax  cut  up  in  small 
pieces.  The  mixture  should  be  warm  but  not  hot  when  used. 
Before  applying  the  composition,  the  plaster  casts  should  be 
well  brushed  with  oil.  The  following  composition  is  recom- 
mended by  Mr.  George  E.  Dunton :  "  Select  10  pounds  of  the 
best  cabinetmaker's  glue  and  put  it  to  soak  over  night  in  S 
pints  water.  The  semi-plastic  mass  should  be  heated  over  a 
water  bath  until  it  becomes  of  the  consistency  of  thick  syrup. 
To  this  mass  should  be  added  2J/2  pounds  of  a  good  quality 
of  molasses  and  i  pound  of  pure  glycerin,  and  thoroughly 
incorporated  by  stirring.  The  molasses  and  glycerin  must  not 
be  added  until  within  one-half  hour  from  the  time  the  compo- 
sition is  to  be  poured.  Never  try  to  make  up  this  composition 
in  a  kettle  sitting  directly  over  the  blaze  of  a  fire."  This 
composition  is  suitable  for  obtaining  a  reverse  mold  of  objects 
which  may  not  themselves  be  suspended  in  the  bath.  When 
the  mold  has  been  obtained,  a  duplicate  of  the  original  should 
be  made  by  pouring  wax  into  the  elastic  mold.  This  wax  cast 
may  be  suspended  in  the  bath  and  deposited  upon,  thus  secur- 
ing a  metallic  reverse  upon  which  a  duplicate  of  the  original 
may  be  deposited. 

MOLDING  PRESSES,  HYDRAULIC.— The  hydraulic 
molding  presses  in  one  of  the  larger  electrotyping  establish- 
ments in  New  York  are  operated  by  accumulators,  in  which  a 
pressure  of  1,000  pounds  to  the  square  inch  is  maintained  by  a 
suitable  pump.  When  the  pressure  in  the  accumulators  reaches 
one  thousand  pounds  an  automatic  governor  stops  the  pump, 
which  starts  again  when  the  pressure  is  diminished  by  reason 
of  the  operation  of  the  presses.  Pressure  is  applied  to  the 
presses  by  simply  turning  a  valve,  and,  as  the  pressure  is  con- 
tinuous, the  travel  of  tiie  press  bed  is  much  more  rapid  than  is 
the  case  when  the  pump  is  attached  to  the  press.  The  plant 
would  be  considered  very  expensive  by  most  electrotypers,  and 


ELECTROTYPING.  '  191 

for  that  reason  this  method  of  molding  is  not  likely  to  become 
popular. 

MOLDING  WAX,  TO  SOFTEN.— A  new  composition 
for  softening  wax  which  has  become  dry  and  brittle  has 
recently  been  put  on  the  market  and  is  sold  by  dealers  in  elec- 
trotyping  supplies.  It  is  called  Ozo  Compound,  and  is  highly 
recommended  by  many  electrotype  molders. 

MOLDS,  BLISTERED.— Blisters  are  sometimes  due  to 
moisture  in  the  wax.  It  may  be  due  to  adulteration.  The 
trouble  may  be  partially  remedied  by  burning  down  the  case 
before  molding.  Skimming  the  case  with  a  hot  wire  will  also 
help  to  remove  the  moisture. 

MOLDS,  COATING.— When  spots  appear  on  the  molds 
which  do  not  coat  readily,  the  difficulty  may  be  due  to  the  fact 
that  the  mold  has  not  been  thoroughly  wetted,  and  may  be 
remedied  by  using  stronger  alcohol  or  a  more  powerful  stream 
of  water.    Greasy  iron  filings  might  also  cause  the  trouble. 

NICKEL  ELECTROTYPES.— To  deposit  nickel  on  wax 
molds,  blacklead  the  mold  in  the  usual  manner  and  increase 
the  conductivity  by  floating  the  surface  of  the  mold  with  a 
solution  made  by  dissolving  phosphorus  in  wood  alcohol  to 
saturation.  After  floating  the  mold  with  the  phosphorus  solu- 
tion, rinse  in  running  water  and  repeat  the  operation.  Mold 
will  cover  in  five  minutes,  and,  after  ten  minutes,  may  be 
removed  from  the  bath,  rinsed  and  immediately  placed  in  the 
copper  bath.  An  interesting  invention  comes  from  Louis 
Boudreaux,  of  Paris,  France.  In  order  to  produde  electrotypes 
in  nickel,  he  covers  the  wax  (before  taking  the  impression) 
with  powdered  bronze,  the  coating  with  graphite  being  omitted. 
In  this  way  he  secures  a  surface  of  wax  that,  when  placed  in 
the  bath,  will  permit  the  adhesion  of  the  nickel  and  result  in 
the  quick  building  up  of  a  shell.  As  is  well  known,  if  electro- 
plating is  undertaken  with  nickel,  after  the  manner  of  copper, 
the  small  amount  of  adhesion  of  the  nickel  to  the  graphite 
often  causes  a   failure.     The  inventor  further  claims  that  a 


1 92  ELECTROT  Y  PING. 

metallic  surface,  as  of  bronze,  on  the  wax  is  much  better  for 
electroplating  with  any  metal  than  is  the  plumbago  surface. 

NICKEL-PLATING  ELECTROTYPES.—  In  printing 
from  electrotypes  with  colored  inks,  more  especially  with  inks 
which  are  prepared  from  a  mercurial  pigment,  such  as  red, 
brown  or  vermilion,  not  only  is  the  surface  of  the  electrotype 
injuriously  affected  by  the  mercury  forming  an  amalgam  with 
the  copper,  but  the  brilliant  colors  are  also  seriously  impaired 
by  the  decomposition  which  occurs.  To  avoid  this,  it  is  best 
to  give  electrotypes  to  be  used  for  such  purposes  a  coating  of 
nickel,  which  effectually  protects  the  copper  from  wear  and 
the  action  of  the  mercury,  and  seemingly  brightens  the  color 
of  the  ink.  It  is  absolutely  necessary  that  the  face  of  the 
electrotype  should  be  chemically  clean,  in  order  that  the  nickel 
deposit  may  adhere  to  the  copper.  After  printing-plates  have 
been  nickeled,  they  should  be  rinsed  in  clear  water,  then 
plunged  in  hot  water  and  dried  in  sawdust.  It  is  claimed  that 
nickeled  plates  will  take  ink  better  if  they  are  also  brushed  with 
fine  whiting. 

NICKEL-PLATING  HALF-TONES.— There  appear  to 
be  conflicting  opinions  regarding  the  nickel-plating  of  half- 
tones, the  usual  impression  being  that  the  cut  becomes  filled 
up.  While  this  may  be  true  to  a  certain  extent,  the  effect  so 
produced  is  far  less  than  is  generally  supposed.  This  may  be 
determined  by  depositing  a  good  plating  of  nickel  on  one  por- 
tion of  a  first-class  electrotype  and  comparing  the  plated  and 
unloaded  portions  under  the  microscope.  Some  nickel-plated 
electrotypes,  made  for  the  purpose  of  determining  this  point, 
appeared  to  be  equally  as  sharp  as  nickeltypes  from  the  same 
originals,  the  amount  of  nickel  on  the  plated  cuts  being  con- 
siderable, .001  inch  or  more,  as  judged  by  the  time  and  current. 
The  reason  of  this  may  be  found  in  the  fact  that  nickel  deposits 
in  a  very  smooth  condition,  and  that  the  current  densities 
during  plating  being  greater  at  points  nearest  the  anode,  more 
metal  would  be  deposited  upon  the  printing  surface  than  in 
the  depth  of  the  dots,  thus,  if  anything,  increasing  the  depth 
of  the  half-tone  plate.     Deterioration,  if  any  occurs,  would 


ELECTROTYPING.  193 

seem  to  be  due  to  a  decrease  in  the  diameter  of  the  dots  in 
the  half-tones  and  the  accumulation  of  nickel  on  the  high- 
light points,  causing  the  impression  in  printing  to  be  darker. 
In  practice,  it  is  doubtful  if  such  an  effect  could  be  noticed. 

NICKEL  SOLUTION.—  The  following  formula  is  recom- 
mended by  Dunton :  To  make  a  solution  in  which  nickel  will 
be  deposited  as  near  faultlessly  as  it  is  possible  in  an  alkaline 
bath,  the  proportion  of  the  nickel-ammonium  sulphate  should 
be  J/2  pound  to  the  gallon  of  boiling  water,  and  make  this 
volume  of  water  slightly  less  than  the  bulk  of  the  desired 
solution  is  to  be.  If  the  solution  is  to  be  12  gallons,  dissolve 
5  pounds  of  the  sulphate  in  10  gallons  of  boiling  water,  stir- 
ring until  the  sulphate  is  all  dissolved ;  then  strain  off  into 
the  tub,  and  add  2  gallons  of  cold  water.  Allow  it  to  stand 
until  the  temperature  has  fallen  to  70°,  and  test  with  the 
hydrometer.  If  it  registers  5°,  or  even  a  half  degree  less, 
it  is  in  condition  to  work;  but  if  more  than  that,  it  must  be 
reduced  with  cold  water  to  that  point,  to  obtain  the  best 
results.  Outside  of  the  advised  addition  of  certain  organic 
acids,  certain  theorists  have  recommended  the  addition  of  all 
kinds  of  nitrates,  sulphates,  carbonates,  citrates,  sodium,  mag- 
nesium, potassium  and  calcium  chlorids ;  but,  as  the  result  of 
my  personal  experiment,  I  would  advise  the  reader  to  leave 
them  all  entirely  out  of  his  prospective  nickel  baths.  The 
results  without  their  addition  will  be  far  more  satisfactory. 
The  nickel  bath  will  be  found  quite  a  troublesome  customer 
to  keep  in  sorts,  as  it  is  supposed  to  be  kept  at  a  state  of 
neutrality  that  is  neither  alkaline  nor  acid ;  if  either,  I  believe 
it  should  show  a  very  slight  acid  reaction.  This  state  may  be 
tested  for,  and  proved,  by  the  ordinary  "  litmus  paper,"  which 
should  be  always  kept  handy  to  the  tub.  Either  the  blue  or 
red  will  answer  the  purpose  equally  well.  If  the  red  is  used, 
first  dip  in  strong  ammonia,  which  will  turn  it  a  deep  blue, 
proving  that  the  ammonia  is  strongly  alkaline.  Allow  the 
paper  to  dry  (it  will  retain  the  blue  color)  ;  now  dip  it  in  the 
solution  and  allow  to  dry.  If,  upon  drying,  the  color  has 
.changed  to  a  reddish  purple,  between  the  red  and  the  blue, 

13 


194  ELECTROTYPING. 

in  which  neither  predominates,  the  sohition  will  yield  the  best 
results.  If  it  should  turn  a  reddish  tint  as  soon  as  drawn 
from  the  liquid,  rest  assured  there  is  too  much  acid  in  the 
solution,  and  the  deposit  will  peel.  If  the  paper  retains  its 
blue,  the  solution  is  too  alkaline  and  will  yield  a  deposit  which 
will  prove  too  brittle  or  hard.  A  very  slight  reaction  toward 
the  red  is  prolific  of  the  best  results.  If  the  solution  becomes 
too  acid,  the  addition  of  a  small  quantity  of  ammonium  sulphate 
will  correct  the  fault ;  if  too  alkaline,  the  nickel  sulphate. 
Consequently,  it  is  an  easy  matter  to  keep  the  contents  of  the 
solution  constant.  A  simple  bath,  which  has  been  thoroughly 
tested  in  some  of  the  largest  electrotype  foundries  in  the 
country,  is  made  by  dissolving  the  double  sulphate  of  nickel 
and  ammonia  in  warm  water,  in  the  proportion  of  three- 
quarters  of  a  pound  of  the  salts  in  each  gallon  of  water.  The 
procedure  is  the  same  that  has  been  recommended  for  the 
copper  solution,  i.  e.,  the  salts  should  be  suspended  in  cheese- 
cloth bags  just  under  the  surface  of  the  water  until  entirely 
dissolved,  when  the  solution  should  be  thoroughly  stirred,  and 
is  then  ready  for  use. 

NICKELTYPES. —  Nickeltypes  possess  three  principal 
advantages  over  electrotypes  for  half-tone  reproduction :  First, 
they  are  much  more  durable ;  second,  they  take  ink  better, 
particularly  colored  inks,  and,  third,  the  method  of  their  manu- 
facture is  such  that  there  is  less  danger  of  scratching  or 
injuring  the  mold  than  in  the  ordinary  methods  of  electrotyp- 
ing.  Probably  the  chief  advantage  of  the  nickeltype  is  found 
in  the  fact  that  it  is  not  affected  by  colored  inks,  although  due 
consideration  should  be  given  to  the  other  points  mentioned. 

NICKELTYPING. —  The  proper  anodes  for  the  purpose 
are  so  hard  that  they  are  subjected  to  4,000  degrees  of  heat 
in  casting,  and,  when  coming  in  contact  with  the  sand,  a  thin 
scale  or  coating  is  formed  on  the  outside,  which  causes  irregu- 
lar deposit  and  gives  the  anode  the  appearance  of  being 
veneered  or  plated.  This  outer  covering  also  contains  an 
indefinite  quantity  of  iron  (carbon),  which,  if  liberated  in  the 
solution  to  an  excessive  degree,  will  stratify  the  latter  to  an 


ELECTROTYPING.  19/5 

extent  of  causing  endless  trouble.  Where  this  iron  oxid  comes 
in  contact  with  the  cathode  before  the  shell  is  perfectly  formed, 
further  development  is  checked,  and  the  next  deposit,  or  back- 
ing, comes  through  to  the  face,  giving  a  faulty  plate,  the  sur- 
face either  being  rough  or  copper  specks  and  spots  showing 
through.  If  this  same  oxid  is  allowed  to  dry  or  adhere  to  the 
nickel  shell  after  it  is  perfectly  formed,  the  copper  or  tinfoil 
will  not  unite  perfectly,  and  the  shell  will  be  lost  and  blister 
or  peel  oflf.  These  are  the  genuine  blisters,  and  should  not  be 
confounded  with  the  so-called  globular  and  irregular  blisters 
that  arise  when  depositing  the  nickel  shell.  These  are  not 
blisters,  but,  more  properly,  gas-blows,  caused  by  the  current, 
solution,  anode  and  cathode  surface  exposed  not  harmonizing. 
A  certain  amount  of  effervescence  during  deposition  is  neces- 
sary to  insure  quick,  bright  and  perfect  deposit;  too  little 
retards  the  work;  too  much  produces  the  defects  mentioned, 
which  are  next  to  impossible  to  eradicate  after  the  shell  is 
backed  up,  especially  in  half-tones. 

NICKELTYPING,  CONNECTIONS  FOR.— In  deposit- 
ing nickel  on  wax  molds,  it  is  desirable  that  the  mold  shall  be 
covered  as  quickly  as  possible.  To  promote  this  end,  it  is 
well  to  extend  a  loop  of  wire  entirely  around  the  mold,  sinking 
it  into  the  wax  and  having  it  long  enough  so  that  the  ends 
may  be  bent  into  hooks  for  suspending  the  mold  in  the  bath. 
By  observing  this  method,  deposition  will  begin  on  all  sides 
of  the  molds  at  once,  instead  of  beginning  at  the  top  and 
spreading  down  over  the  entire  length  of  the  mold,  as  is  the 
case  when  the  ordinary  electrotyping  connection  is  employed. 
With  the  loop-wire  method,  the  mold  will  cover  in  from  two 
to  three  minutes. 

NICKELTYPES,  DEFECTIVE.—  Depressions  in  the  face 
of  nickeltype  plates  are  due  to  gas  bubbles,  caused  usually  by 
too  strong  a  current.  Nickeltyping  is  not  an  easy  proposition, 
and,  to  be  successful,  all  the  conditions  must  be  just  right.  The 
current  and  solution  must  harmonize.  To  ascertain  the  proper 
strength  of  current  is  a  matter  of  experiment,  and  for  this 


196  ELECTROTYPING. 

purpose  depositing  apparatus   should   include  a   rheostat,  by 
means  of  which  the  current  may  be  varied  at  will. 

OZO  COMPOUND.— The  quantity  of  ozo  compound  to 
be  added  to  the  molding  wax  or  ozokerite  varies  with  the 
season  of  the  year  and  the  condition  (or  quality)  of  the  wax. 
Start  with  from  one  pint  to  one  quart  to  each  fifty  pounds  of 
wax,  adding  more  until  the  wax  is  soft  enough.  Most  of  the 
ozokerite  in  use  is  of  inferior  grades.  The  less  pure  ozokerite 
is  the  more  crude  oil  it  contains  and  the  lower  its  melting 
point,  requiring  less  ozo  compound.  Beware  of  an  overdose, 
as  it  takes  some  time  to  get  the  wax  into  shape  in  case  of  an 
overdose.  The  best  molds  are  made  with  pure  ozokerite 
reduced  with  ozo  compound.  Never  heat  the  forms,  and  use 
cold  cases  or  molds.  In  lifting  forms  out  of  the  mold,  give  a 
steady,  strong  pull.  The  form  will  not  release  quite  so  easily 
from  a  cold  case  as  from  a  heated  case,  but  the  results  will  be 
better  from  the  cold  case. 

OZOKERITE,  TO  SOFTEN.— When  ozokerite  molding 
composition  becomes  hard  and  brittle,  add  vaseline,  or  ozo 
compound,  a  little  at  a  time,  until  it  becomes  sufficiently  soft 
and  plastic. 

OZOKERITE,  TO  HARDEN.— In  hot  weather,  if  the 
composition  becomes  too  soft,  add  a  very  little  of  pine  tur- 
pentine. 

PATINA,  IMITATION  OF  GENUINE.— Repeatedly 
brush  the  objects  with  solution  of  sal  ammoniac  in  vinegar, 
the  action  of  the  solution  being  accelerated  by  the  addition  of 
verdigris.  A  solution  of  9  drams  of  sal  ammoniac  and  2J4 
drams  of  potassium  binoxalate,  in  i  quart  of  vinegar,  acts  still 
better.  When  the  first  coat  is  dry,  wash  the  object  and  repeat 
the  manipulation,  drying  and  washing  after  each  application, 
until  a  green  patina  is  formed.  It  is  best  to  bring  the  article, 
after  being  brushed  over,  into  a  hermetically  sealed  box,  upon 
the  bottom  of  which  a  few  shallow  dishes  containing  very 
dilute  sulphuric  acid  and  a  few  pieces  of  marble  are  placed. 


ELECTROTYPING.  197 

PEELING,  TO  PREVENT.—  The  great  difficulty  in  nick- 
eltyping  is  peeling  of  the  deposit  before  a  sufficient  thickness 
has  been  attained.  To  prevent  peeling,  the  solution  and  the 
current  must  be  of  just  the  right  strength.  To  enable  the 
operator  to  work  intelligently,  a  voltmeter  and  a  rheostat 
should  be  included  in  the  circuit.  The  current  may  then  be 
suited  to  existing  conditions  and  varied  at  the  will  of  the 
workman.  Nickel  is  a  somewhat  obstinate  metal  to  deposit, 
and  requires  careful  attention.  It  will  not  adhere  to  surfaces 
which  are  not  absolutely  clean,  and  even  then  will  peel  if  left 
in  the  bath  too  long,  or  if  deposited  with  too  strong  a  current. 
The  printing  surfaces  which  are  to  be  nickeled  should  be 
scrubbed  with  hot  lye  or  brushed  with  lime  paste,  and  then 
thoroughly  washed  in  running  water,  after  which  they  should 
be  immediately  suspended  in  the  bath.  They  should  not  be 
allowed  to  dry  or  be  touched  with  the  hands ;  with  a  current 
of  two  to  three  volts  tension,  fifteen  or  twenty  minutes  in  the 
bath  will  be  sufficient.  The  plates  should  be  separated  from 
the  anode  by  a  distance  of  six  or  seven  inches. 

PINHOLES. —  Shells  which  are  defective  by  reason  of 
"  pinholes  "  are  very  annoying.  The  usual  cause  is  insufficient 
blackleading,  or  failure  to  blow  out  the  lead  thoroughly  after 
the  mold  has  come  out  of  the  machine.  There  are  other 
causes,  however,  among  which  may  be  mentioned  the  forma- 
tion of  gas  bubbles  in  the  depressions  of  the  mold,  and  an 
insufficiency  of  acid  in  the  solution  when  working  with  a  very 
strong  current.  The  second  cause  may  be  remedied  by  employ- 
ing an  agitator.  The  remedy  for  the  first  and  third  causes  is 
self-evident. 

PLATING  WITHOUT  A  BATTERY.— Simple  immer- 
sion of  an  iron  article  in  an  ordinary  solution  of  copper  sul- 
phate, such  as  is  employed  in  electrotyping,  will  produce 
sufficient  action,  chemical  or  electrotlytic,  or  both,  to  form  a 
very  thin  coating  of  copper  on  the  iron.  Steel  pens,  needles, 
etc.,  are  coppered  by  revolving  them  in  a  tumbling-box  with 
sawdust  moistened  with  a  solution  made  by  dissolving  i^ 
ounces  of  blue  vitriol  in  lo  quarts  of  water,  and  adding  i^ 


198  ELECTROTYPING. 

ounces  of  pure  sulphuric  acid.  Brush  coppering  is  executed 
as  follows :  The  utensils  required  are  two  vessels  of  sufficient 
size,  each  provided  with  a  brush.  One  vessel  contains  a 
strongly  saturated  solution  of  caustic  soda,  and  the  other  a 
strongly  saturated  solution  of  blue  vitriol.  The  well-cleansed 
object  is  first  uniformly  coated  with  the  caustic  soda  and  then 
with  the  blue  vitriol.  A  quite  thick  film  of  copper  is  immedi- 
ately deposited.  Care  must  be  taken  not  to  take  the  brush  too 
full,  and  not  to  touch  a  second  time  the  place  once  gone  over, 
as  otherwise  the  copper  will  not  adhere  firmly. 

POSTAGE  STAMP  PLATES.— The  United  States  post- 
age stamps  are  printed  on  a  steam  press,  from  steel  plates,  and 
not  from  electrotypes.  The  original  is  engraved  on  soft  steel 
and  then  casehardened,  and  this  hardened  die  or  original  is 
pressed  into  the  rim  of  a  soft  steel  roller,  which  is  also  case- 
hardened,  and  from  this  hardened  roller  any  number  of  dupli- 
cates are  made  on  soft  steel,  which  are  again  hardened  before 
printing. 

RAPID  ELECTROTYPING.— Mr.  J.  A.  Corey,  manager 
of  the  electrotyping  department  of  His  Majesty's  printing- 
office,  claims  to  have  invented  a  depositing  apparatus  which 
enables  him  to  successfully  employ  220  amperes  per  square 
foot.  No  more  time  is  required  to  prepare  the  mold  for  the 
bath  than  is  usually  necessary.  He  hopes  soon  to  be  able  to 
give  the  trade  full  particulars  of  this  depositor.  The  full  sig- 
nificance of  Mr.  Corey's  announcement  may  be  realized  when 
it  is  remembered  that  the  average  electrotyper  employs  from 
forty  to  seventy-five  amperes  per  foot.  Mr.  Corey's  invention, 
if  practical,  would  reduce  about  two-thirds  the  time  at  present 
required  ior  depositing. 

RESISTANCE. —  Resistance  is  that  quality  in  an  object 
which  prevents  more  than  a  certain  amount  of  current  passing 
through  it  in  a  given  time,  when  impelled  by  a  given  electro- 
motive force.  The  resistance  of  a  conductor  is  equal  to  the 
time  required  for  a  unit  quantity  of  electricity  (i.  e.,  a 
coulomb)  to  pass  through  it,  while  its  two  ends  are  maintained 
at  a  unit  diflference  of  potential,  i.  e.,  at  one  volt.     The  unit 


ELECTROTYPING.  199 

of  resistance  is  termed  an  ohm.  The  resistance  of  liquids  as 
compared  with  metals  is  enormous,  the  resistance  of  a  satu- 
rated solution  of  blue  vitriol  being  16,885,520  times  greater 
than  copper.  The  resistance  of  a  wire  is  directly  proportional 
to  its  length,  and  inversely  to  its  sectional  area  or  weight,  per 
unit  of  length.  Conductivity  is  the  reverse  of  resistance.  By 
rise  of  temperature,  the  conductive  resistance  of  metals  is 
increased,  and  of  electrolytes  is  decreased;  thus  warm  solu- 
tions facilitate  deposition. 

RESISTANCE  BOARD.— The  switchboard,  or  resistance 
board,  consists  of  a  number  of  metallic  spirals,  usually  of  Ger- 
man silver,  arranged  on  a  board  in  such  a  manner  that  one 
or  more  of  them  may  be  switched  into  the  circuit,  thus  pre- 
senting more  or  less  resistance,  as  may  be  desired,  to  the 
passage  of  the  current. 

REVERSE  ELECTROTYPING.— To  prevent  the  deposit 
from  adhering  to  a  metallic  matrix,  clean  the  matrix  thor- 
oughly and  then  flow  over  it  a  very  weak  solution  of  potas- 
sium sulphuret.  An  impalpable  film  will  effectually  prevent 
adhesion  of  the  deposit.  This  process  is  found  very  useful  in 
the  production  of  reverses  and  in  the  manufacture  of  embos- 
sing dies. 

SAWS,  CARE  OF. —  Royle  says:  If  new  saws  do  not 
run  true  sideways,  get  the  manufacturers  of  them  to  remedy 
the  trouble.  The  eye  of  the  saw  should  always  fit  the  mandrel 
nicely.  Never  use  a  hammer  on  the  spindle  nut  —  a  wrench  is 
provided  especially  for  this  nut.  A  piece  of  emery  wheel  or 
grindstone  is  good  for  truing  up  a  saw.  Do  not  use  a  saw 
that  is  out  of  round.  See  that  every  tooth  in  the  saw  cuts. 
To  set  a  saw  truly,  much  care  is  needed.  Avoid  too  much  set. 
Set  over  only  the  points  of  the  teeth.  Use  as  little  set  as 
possible.  Never  use  a  nail  punch  for  setting.  Work  with  a 
sharp  saw.  Don't  be  stingy  with  saws;  keep  an  assortment. 
Specially  good  workmen  should  have  saws  for  their  special 
use.  Change  saws  to  suit  the  work  required  —  remember  that 
this  can  be  readily  done.  The  smaller  saw  that  is  suitable  is 
the  preferable  one  to  use.     A  sharp,  true  saw  is  required  for 


200  ELECTROTYPING. 

good  work.  A  dull  saw  is  a  dangerous  one.  Avoid  a  high 
ripping  gauge,  or  fence,  when  a  low  one  will  answer.  Before 
ripping  stuff,  try  the  ripping  gauge  to  see  if  it  is  parallel  with 
the  saw.  A  good  test  of  this  is  to  rip  a  short  piece  to  a 
width,  and  see  if,  as  it  passes  through,  it  just  glides  along  the 
edge  of  the  saw-blade,  touching  it  lightly.  Adjust  the  table 
top  so  that  the  saw  will  just  reach  through  the  stuff.  While 
sawing,  keep  your  eyes  on  your  work.  Use  great  caution,  but 
avoid  timidity.  A  smoking  saw  needs  sharpening.  Flying 
smoke  means  trouble  for  the  saw.  Burnt  and  buckled  saws 
indicate  carelessness.  A  buckled  saw  is  a  bad  one.  Screech- 
ing saws  have  long  teeth.  Avoid  high  or  long  teeth.  Joint 
off  the  saw  frequently,  and,  when  you  do  so,  remove  it  to  the 
clamps  for  filing.  File  straight  across.  In  filing,  first  sharpen 
the  face  or  front  of  the  tooth,  then  file  off  the  back  of  the 
same  tooth.  Save  time  by  filing  from  one  side.  Different 
persons  should  not  file  the  same  saw.  Why  use  a  fleam-toothed 
saw  for  crosscutting  when  a  fine-tooth  rip  will  answer?  Try 
it.  Fleam  teeth  are  unnecessary  except  for  special  work.  Too 
thin  saws  will  screech  and  run.  A  good  sawyer  is  known  by 
the  saws  that  he  keeps.  Avoid  a  worn  throat-piece  —  renew  it 
frequently.  Most  accidents  arise  from  carelessness.  Have  the 
belt-shifter  work  freely;  control  it  with  the  foot.  It  is  essen- 
tial that  the  belts  be  even  in  thickness  throughout  their  entire 
length.  The  spindle  belt,  at  least,  should  have  no  rivets  or 
lacings;   all  joints  should  be  lap-glued  or  cemented. 

SERIES,  ELECTROTYPING  IN.— There  is  no  object  in 
connecting  two  tanks  in  series  unless  you  use  twice  the  E.  M. 
F.  you  would  on  one  tank.  The  primary  advantage  in  con- 
necting tanks  in  series  is  found  in  the  general  principle  of 
electric  distribution  —  that  a  given  amount  of  power  or  energy 
is  conveyed  more  cheaply  at  a  high  pressure  than  at  a  low 
pressure.  Next,  it  is  easier  to  build  a  machine  of  a  given 
capacity  for  high  pressure  and  low  current  than  for  low  pres- 
sure and  high  current.  The  current  capacity  of  a  dynamo  is 
determined  by  the  cross-section  of  the  armature  conductors. 
A  four-pole  armature  wound  with  J<2-inch  copper  rods  has  a 


ELECTROTYPING.  201 

capacity  of  1,500  amperes.  It  will  get  too  hot  on  a  high  cur- 
rent. Suppose  you  are  working  quiet  solutions :  i  volt  is 
enough  E.  M.  F.  per  tank,  and  20  amperes  per  square  foot 
of  cathode,  we  will  say,  is  the  current  required.  If  this  1,500- 
ampere  armature  is  revolved  in  such  a  field  and  such  a  speed  as 
to  develop  or  generate  i  volt,  it  is  evident  that  tanks  in  parallel 
only  can  be  used  —  or  one  big  tank.  The  surface  that  can  be 
covered  at  a  maximum  rate  is  1,500  divided  by  20,  or  75  square 
feet.  If,  however,  this  same  armature  be  revolved  in  such  a 
field  and  at  such  a  speed  as  to  generate  2  volts,  its  current 
capacity  will  in  no  wise  be  affected,  and  you  can  use  the  cur- 
rent twice  over,  consuming  i  volt  in  its  first  passage  through 
the  solution,  and  the  remaining  i  volt  in  its  second  passage, 
and  so  on.  If  a  1,500-ampere  armature  be  revolved  in  a  field 
which  will  produce  10  volts,  a  corresponding  number  of  tanks 
can  be  operated,  each  depositing  for  a  maximum  on  75  square 
feet  of  surface.  A  water-power  may,  perhaps,  give  a  simple 
analogy.  Suppose  1,000  cubic  feet  per  minute  is  flowing  in  a 
given  stream.  It  is  evident  that,  with  20-foot  fall  or  head, 
twice  the  work  can  be  accomplished  that  can  be  with  a  lo-foot 
head.  From  the  fact  that  the  E.  M.  F.  of  an  armature  is 
dependent  on  three  things,  namely,  turns  of  armature,  strength 
of  field,  and  velocity,  it  follows  that  an  armature  built  for 
1,500  amperes  and  i  volt  can  not  be  used  for  1,500  amperes 
and  5  volts,  without  making  an  enormously  large  field  and 
running  it  at  a  prohibitory  speed.  Therefore,  a  change  in  E. 
M.  F.  above  25  per  cent,  on  small,  slow-speed  machines, 
demands  a  rearrangement  of  parts  and  different  windings. 
There  is  no  object  in  taking  a  dynamo  of  3  volts  or  less  and 
putting  it  on  two  tanks  either  in  series  or  in  parallel,  for,  if 
the  solution  be  agitated,  the  entire  3  volts  may  be  used  in 
one  tank. 

SILVER  ELECTROTYPING.— Silver  is  occasionally 
used  in  special  cases  for  copying  works  of  art  or  even  valuable 
engraved  steel  plates.  Ordinary  wax  and  gutta-percha  molds, 
such  as  are  used  for  copper  electrotyping,  are  not  admissible 
for  silvering,  because  they  are  to  some  extent  attacked  by  the 


202  ELECTROTYPING. 

cyanid  solutions.  The  simplest  method  of  obtaining  replicas  of 
works  of  art  in  silver  is  to  obtain,  first,  a  thin  electrotype  shell 
of  copper  from  the  intaglio  mold,  and  then  to  deposit  silver 
upon  this  in  the  cyanid  bath.  The  copper  protecting  film  may 
be  of  the  thinnest,  so  that  it  shall  not  destroy  the  sharpness 
of  the  lines,  but  it  must,  of  course,  be  subsequently  removed, 
after  the  required  thickness  of  silver  has  been  deposited,  and 
the  whole  electro  separated  from  the  mold.  This  solution  of 
the  copper  may  be  effected  by  treatment  with  warm  hydro- 
chloric acid,  or,  better,  with  a  warm  solution  of  iron  per- 
chlorid,  either  of  which  will  attack  the  copper  but  leave  the 
silver  untouched.  On  the  removal  of  the  copper,  the  pure 
silver  surface  has  the  required  form  in  practically  undimin- 
ished sharpness  and  brilliancy.  The  silver  may  be  built  up 
to  a  thickness  of  one-eighth  of  an  inch  or  more.  It  is  seldom, 
however,  that  this  process  is  required,  and  practically  the  sole 
application  of  electro-silvering  is  -to  be  found  in  the  coating 
of  other  metals  to  endow  them  with  properties  which  they  do 
not  themselves  possess. 

SILVERING  SOLUTION  FOR  GLASS.— (i)  Nitrate  of 
silver,  i  ounce;  water,  lo  ounces;  add  liquid  ammonia  until 
the  brown  precipitate  is  redissolved ;  then  add  90  ounces 
water.  (2)  A  i  per  cent  solution  of  formaldehyde.  Mix  two 
parts  of  I  with  one  part  of  2.  Flood  the  surface  to  be  silvered. 
In  fifteen  to  twenty  minutes  wash  in  running  water. 

SOLUTION,  CONDUCTIVITY  OR— It  should  be 
remembered  that  the  solution  is  a  conductor  of  the  current  in 
the  same  sense  that  the  rods  are,  and  should  be  considered  in 
that  capacity  as  well  as  a  dissolving  medium.  Pure  sulphate 
of  copper  solution  is  an  extremely  poor  conductor.  The  addi- 
tion of  sulphuric  acid  improves  its  conductivity,  but  under  the 
most  favorable  conditions  its  resistance  is  several  milKons  of 
times  greater  than  copper.  To  reduce  this  resistance  to  a  point 
where  the  liquid  will  not  become  appreciably  heated  by  the 
passage  of  a  strong  current,  it  is  necessary  to  provide  an 
exceedingly  large  area  of  conducting  fluid  and  to  suspend  the 
anodes  and  cathodes  as  near  together  as  possible,  say  two  or 


ELECTROTYPING  203 

three  inches  apart.  According  to  Joule's  law,  the  develop- 
ment of  heat  will  be  greater  the  smaller  the  cross  section  of 
the  conductor  and  conducting  capacity  are,  and  the  larger  the 
quantity  of  current  which  passes  through  it.  If,  therefore, 
it  is  desired  to  employ  a  very  strong  current,  the  vat  must  be 
larger  in  proportion  to  the  size  of  the  anodes  than  would  be 
necessary  with  a  moderate  current. 

SOLUTION,  COPPER,  HOW  TO  ASSAY.— There  are 
two  ways  of  measuring  the  content  of  copper  in  a  solution, 
both  of  which  require  accurate  instruments  and  the  facilities 
of  a  laboratory.  The  simplest  and  best  method  is  that  of 
electrolysis.  A  very  delicate  and  accurate  scale  is  required, 
capable  of  measuring  i-ioo  of  a  grain.  The  process  is 
described  by  McMillan  as  follows :  "  A  platinum  dish  about 
three-quarters  of  an  inch  to  an  inch  in  height,  and  about  three 
inches  in  diameter,  forms  a  convenient  cathode,  at  once  hold- 
ing the  solution  and  receiving  the  deposited  metal.  The  anode 
consists  of  a  circular  plate  of  stout  platinum  foil  about  2^ 
inches  in  diameter,  with  several  perforations  to  allow  gas  to 
escape  from  beneath  it.  The  platinum  sheet  is  fastened  hori- 
zontally, without  solder,  to  the  end  of  a  vertical  platinum  wire, 
attached  to  the  positive  pole  of  the  battery,  the  platinum  dish 
making  contact  externally  with  a  copper  wire  attached  to  the 
negative  pole.  Instead  of  this,  a  cylinder  of  platinum  foil 
may  be  used  as  a  cathode,  being  suspended  with  its  main  axis 
vertical  within  a  small  beaker,  the  anode  consisting  of  a  coil 
of  platinum  wire  placed  within  the  cathode.  The  object  of 
the  electrolysis  method  is  to  continue  the  action  of  the  current 
until  every  trace  of  copper  is  precipitated  on  the  platinum 
cathode,  and,  as  the  latter  should  have  been  weighed  pre- 
viously, the  increase  of  weight  shown  after  deposition  gives 
the  number  of  grains  of  metal  in  the  quantity  of  solution  taken. 
It  is  possible  to  separate  every  trace  of  copper  from  the  solu- 
tion, so  this  method  rhay  be  made  to  give  absolutely  accurate 
results.  Half  an  ounce  of  the  liquid  may  be  employed,  and 
electrolysis  is  continued  until  the  liquid  is  decolorized  and  a 


204  KLECTROTYPING. 

drop  removed  from  it  strikes  no  blue  color  with  an  excess  of 
ammonia." 

SOLUTION,  HOT,  REMEDY  FOR.— Heating  of  the 
solution  is  caused  by  resistance.  This  is  always  the  cause  of 
heat,  and  the  way  to  minimize  resistance  is  to  increase  the 
capacity  of  the  conductors.  The  solution  is  a  conductor  of 
the  current  from  the  anode  to  the  cathode.  It  is  a  very  poor 
conductor,  however,  as  all  solutions  are,  and  must,  therefore, 
have  a  large  area  to  compensate  for  what  it  lacks  in  quality. 
Under  ordinary  conditions  the  cross-sectional  area  of  the  solu- 
tion should  be  at  least  twice  as  great  as  the  area  of  the  anode ; 
with  a  very  strong  current,  the  cross-sectional  area  of  the  solu- 
tion should  be  at  least  three  times  that  of  the  anode.  In  other 
words,  if  the  anode  is  15  by  20  inches,  the  vat  should  be  32 
inches  wide  and  the  solution  28  inches  deep.  A  current  of 
sufficient  strength  to  deposit  good  shells  in  one  hour  requires 
large  conductors,  and  this  applies  not  only  to  the  copper  rods 
but  to  the  solution,  which  is  also  a  conductor.  Moreover,  the 
solution  is  a  very  poor  conductor,  and  what  it  lacks  in  respect 
of  quality  must  be  made  up  so  far  as  possible  in  quantity.  The 
cross-sectional  area  of  the  solution  should  be  from  two  to 
three  times  the  area  of  the  case. 


ELECTROTYPING. 


205 


SOLUTIONS,    SPECIFIC    GRAVITY    OF,    CORRESPONDING    TO 
THE  DEGREES   OF  THE   BAUME  HYDROMETER. 


Degree 

Specific 

Degree 

Specific 

Degree 

Specific 

Degree 

Specific 

Baume. 

Gravity. 

Baume. 

Gravity. 

Baume. 

Gravity. 

Baume. 

Gravity. 

o 

I.OOO 

19 

1. 147 

37 

1-337 

55 

1.596 

I 

1.007 

20 

I    157 

38 

1-349 

56 

1. 615 

2 

1. 014 

21 

1. 166 

39 

1. 361 

57 

1-634 

3 

1.020 

22 

1. 176 

40 

1-375 

58 

1.653 

4 

1.028 

23 

1. 185 

41 

1.388 

59 

1. 671 

5 

1.034 

24 

1. 195 

42 

1. 401 

60 

1.690 

6 

1. 041 

25 

1.205 

43 

1. 414 

61 

1.709 

7 

1.049 

26 

1. 215 

44 

1.428 

62 

1.729 

8 

I  057 

27 

1.225 

45 

1.442 

63 

1-750 

9 

1.064 

28 

1-235 

46 

1-456 

64 

1. 771 

lO 

1.072 

29 

1.245 

47 

1.470 

65 

1-793 

II 

1.080 

30 

1.256 

48 

1.485 

66 

1. 815 

12 

1.088 

31 

1.267 

49 

1.500 

67 

1.839 

13 

1.096 

32 

1.278 

50 

1. 515 

68 

1.864 

14 

1. 104 

33 

1.289 

51 

1. 531 

69 

1.885 

15 

1. 113 

34 

1.300 

52 

1.546 

70 

1.909 

i6 

1. 121 

35 

1. 312 

53 

1.562 

71 

I  935 

17 

I.  130 

36 

1.324 

54 

1.578 

72 

1.960 

i8 

1. 138 

Note. —  The  specific  gravity  of  a  solution  is  rapidly  ascertained  by 
floating  a  hydrometer  in  it.  This  instrument  sinks  deeper  in  solutions 
of  low  density  than  in  those  of  high  gravity,  and  the  actual  gravity  is 
found  by  the  level  at  which  the  liquid  stands  on  the  graduated  portion 
when  the  apparatus  is  floating  freely  in  it.  Hydrometers  of  this  kind 
are  sometimes  graduated  so  that  the  specific  gravity  is  read  off  direct 
from  the  scale,  others  are  graduated  by  Baume's  method,  and  the  reading 
may  then  be  converted  into  the  number  representing  the  true  density,  by 
reference  to  the  above  table. 

STATISTICS. —  A  London  writer  states  that  there  are 
fourteen  electrotype  foundries  in  that  city,  whose  total  output 
is  £80,000  (approximately  $400,000)  yearly.  In  Chicago  there 
are  twenty  foundries,  having  an  estimated  output  of  over 
$500,000.  Prices  in  the  two  cities  do  not  differ  materially, 
while  the  population  of  London  is  probably  three  times  that  of 
Chicago.  On  the  basis  of  population,  as  compared  with  Chi- 
cago, London  should  support  sixty  electrotype  foundries  and 
should  produce  $1,500,000  worth  of  electrotypes  annually.  It 
is  evident  that  English  printers  do  not  employ  electrotypes 
as  extensively  as  the  Americans,  and  one  reason  for  this  may 


206  ELECTROTYPING. 

be  found  in  the  popularity  of  stereotyping.  Nearly  every  large 
printing  establishment  operates  a  stereotyping  plant,  and  it  is, 
to  a  certain  extent,  independent  of  the  electrotypers.  In  Chi- 
cago, very  little  job-printing  is  done  from  stereotypes.  Few 
printers  have  facilities  for  doing  their  own  stereotyping,  and, 
when  purchasing  plates,  most  of  them  prefer  to  pay  the  extra 
cost  for  electrotypes. 

SWEATING. —  Shave  the  top  of  the  base  and  the  back  of 
the  plate  so  as  to  have  clean,  smooth  surfaces.  Do  not  shave 
the  bottom  of  the  base.  Brush  over  the  shaved  surface  of  the 
base  with  soldering  fluid,  made  by  dissolving  scraps  of  zinc 
in  muriatic  acid  to  saturation,  and  diluting  with  an  equal  bulk 
of  water.  After  covering  the  surface  of  the  base  with  a  sheet 
of  tinfoil,  place  it  on  an  iron  plate  and  float  it  in  your  metal- 
pot.  When  the  tin  begins  to  melt,  remove  the  base  from  the 
metal-pot,  place  the  electro  upon  it,  and  immediately  clamp 
them  together.  The  back  of  the  electro  should  have  been  pre- 
viously brushed  over  with  the  soldering  fluid.  The  plate  and 
base  may  be  clamped  together  with  an  ordinary  hand  clamp,  or 
more  than  one  if  the  plate  is  large,  first  protecting  the  face 
of  the  plate  by  laying  upon  it  a  piece  of  smooth  board.  In 
this  method  of  blocking,  advantage  is  taken  of  the  fact  that 
tin  fuses  at  a  much  lower  temperature  than  stereotype  or 
electrotype  metal,  and  also  that  clean,  bright  metal  fuses  much 
more  readily  than  old  metal,  or,  strictly  speaking,  metal  which 
has  become  oxidized.  Because  of  this  latter  fact,  it  is  impor- 
tant that  the  bottom  of  the  base  should  not  be  shaved,  as  the 
film  of  oxid  protects  it  to  a  considerable  extent  and  insures  the 
fusing  of  the  tin  before  the  base  metal  is  attacked. 

THREE-COLOR  BLOCKS,  ELECTROTYPES  OR— 
Mr.  J.  S.  Sunderland,  in  "  Penrose's  Pictorial  Annual,"  advises 
that  in  making  electrotypes  of  fine-screen  plates  no  brush 
should  be  allowed  to  come  in  contact  with  the  molded  surface. 
He  produces  a  conducting  surface  by  polishing  the  wax  sur- 
face before  molding,  not  merely  brushing  over  the  case  with 
molding  lead,  but  giving  it  a  real  polish.  Dixon's  and  Mor- 
gan's  polishing   lead    in    equal    proportions    is    recommended. 


ELECTROTYPING.  207 

Cover  the  wax  mold  with  a  sheet  of  paper  while  trimming,  and 
only  blacklead  the  parts  cut  with  the  trimming  knife.  The 
result  will  be  electrotypes  equal  in  every  respect  to  the  origi- 
nals. 

VATS,  GLASS  RAILS  FOR.—  Electrotypers'  depositing 
vats  are  usually  lined  with  lead,  which  is  turned  over  the  top 
edges  of  the  tank  to  guard  against  any  possibility  of  leakage. 
To  insulate  the  rods  from  the  metal  lining,  a  wooden  rail  is 
fitted  over  the  top  edges  of  the  vat  on  top  of  the  lead.  So 
long  as  the  wood  remains  dry,  the  insulation  is  effectual,  but 
eventually  it  becomes  saturated  with  the  solution  and  must  be 
removed.  With  an  agitated  solution,  the  life  of  the  wood  is 
shorter  than  when  a  quiescent  solution  is  employed,  but  in 
either  case  it  is  only  a  question  of  time  when  the  wooden  rail 
will  become  saturated  and  rotten,  and  in  this  condition  it 
becomes  a  conductor  of  the  current  and  creates  a  short  circuit 
which  absorbs  more  or  less  of  the  energy  of  the  current.  The 
life  of  the  rail  may  be  prolonged  by  giving  it  several  coats  of 
waterproof  paint,  but  a  more  cleanly  and  altogether  more 
satisfactory  plan  is  to  substitute  for  the  wooden  rails  strips  of 
heavy  glass  about  one  inch  in  thickness.  Such  strips  may  be 
procured  from  glass  dealers  at  small  expense,  and,  with  a 
couple  of  holes  drilled  and  countersunk  in  each,  to  provide  a 
means  of  securing  them  to  the  vat,  they  furnish  a  neat  and 
serviceable  finish  for  the  vat  and  provide  a  reliable  insulation 
for  the  rods. 

VERDIGRIS,  TO  REMOVE  FROM  ELECTROTYPES. 
—  Acetic  acid  and  table  salt  will  aid  in  removing  the  objection- 
able spots.  First  dissolve  the  salt  thoroughly  in  the  acid.  It 
is  then  ready  for  use.  Use  a  nail-brush  or  tooth-brush  to  apply 
the  wash.  Do  this  carefully  to  avoid  scratching  the  face  of  the 
plates.  This  wash  will  not  remove  the  enamel  from  original 
copper  engravings.  After  cleaning  the  plates,  rub  a  little 
kerosene  over  them  before  and  after  use.  Creosote  will  also 
be  found  a  good  remover  of  verdigris  from  copper  surfaces. 

WASHING  ELECTRO  SHELLS.— Backing  up  electro 
shells  without  washing  is  a  very  objectionable  practice.    Even 


208  ELECTROTYPING. 

when  washed  with  hot  lye  there  is  likely  to  be  some  wax 
remaining,  which  will  be  burned  to  the  backing  pan,  rendering 
it  uneven  and  making  lots  of  trouble  in  finishing  plates. 

WRINKLES  IN  SHELLS.— Wrinkles  in  shells  are 
caused  by  wrinkles  in  the  molds.  Unless  the  molds  are  care- 
fully examined,  they  would  not  be  noticed,  but  close  inspection 
in  a  strong  light  will  detect  them. 

WATT. —  A  watt  is  a  current  of  one  ampere,  at  a  pressure 
of  one  volt;   equal  to  1-746  of  a  horse-power. 

WAX  ENGRAVING. —  The  term  wax  engraving  is,  in  one 
sense,  misleading,  for,  while  wood,  zinc,  copper  and  steel 
engravings  and  etchings  may  be  printed  direct  from  the  origi- 
nals, the  wax  engraving,  like  the  chalk-plate  engraving,  can 
not  be  utilized  direct.  The  wax  engraving  is,  in  fact,  a  mold 
into  or  upon  which  copper  or  other  metal  must  be  deposited 
by  the  electrotyping  process  in  order  to  obtain  a  printing  sur- 
face. To  make  a  wax  engraving,  a  plate  of  copper  or  other 
metal  is  thinly  coated  with  wax.  The  design  which  is  to  be 
reproduced  as  a  printing-plate  is  then  drawn  through  the  wax 
upon  the  plate  beneath.  In  the  reproduction  of  wood  engra- 
vings, zinc  etchings,  etc.,  by  the  electrotype  process,  a  mold  of 
the  object  is  made  by  impressing  it  in  a  bed  of  wax.  The  wax 
mold  is  then  suspended  in  the  depositing  bath,  and  the  deposit 
formed  upon  it  will  obviously  be  an  exact  duplicate  of  the 
original.  But  we  do  not  want  a  duplicate  of  the  wax  engra- 
ving. What  we  do  want  is  a  reverse.  So,  instead  of  making 
a  mold,  we  hang  the  engraving  in  the  solution,  and  deposit 
directly  upon  it.  The  process  of  making  an  electrotype  of  wax 
engraving  from  this  point  on  is  just  the  same  as  making  an 
electrotype  of  any  other  printing  surface.  Previous  to  immer- 
sion in  the  bath,  the  spaces  between  the  engraved  lines  are 
built  up  with  wax.  The  engraving  is  then  blackleaded,  a  film 
of  copper  is  precipitated  upon  it  by  the  iron-filings  process,  to 
increase  the  conductivity  of  the  mold,  and  the  connections 
adjusted.  When  a  shell  of  sufficient  thickness  has  been 
deposited,  it  is  removed  in  the  usual  manner,  backed  up  with 


ELECTROTYPING.  209 

metal,  straightened,  mounted  on  a  wood  or  metal  base,  and  is 
then  ready  for  the  press.        ' 

WAX-KETTLES. —  For  melting  beeswax  or  ozokerite, 
a  steam- jacketed  kettle  should  always  be  employed.  Never 
heat  by  gas  or  fire,  as  there  would  be  great  danger  of  over- 
heating and  spoiling  the  composition. 

WAX  MOLDS,  METALIZING.—  The  following  methods 
of  making  the  surface  of  wax  molds  conductive  are  recom- 
mended by  Langbein,  Urquhart  and  Watt.  Take  equal  parts  of 
albumen  (white  of  egg)  and  a  saturated  solution  of  common 
salt,  and  apply  the  mixture  to  the  mold  by  means  of  a  soft 
brush.  Then  dry  the  surface  thoroughly.  Now  make  a  strong 
solution  of  nitrate  of  silver  and  dip  the  mold  into  it  for  a  few 
minutes,  and  dry  again.  Expose  the  mold  to  a  strong  light 
until  it  becomes  quite  black.  The  mold  is  then  to  be  dipped 
into  a  saturated  solution  of  sulphate  of  iron,  when  a  layer  of 
metallic  silver  will  be  formed,  upon  which  a  deposit  of  copper 
may  be  readily  obtained.  The  mold  should  be  rinsed  when 
taken  from  the  sulphate  of  iron  solution,  and  connecting  wire 
attached  to  it,  when  it  may  at  once  be  placed  in  the  depositing 
bath.  Another  method  is  as  follows :  Dissolve  a  piece  of 
phosphorus  in  a  small  quantity  of  bisulphid  of  carbon.  Stir 
in  two  drams  of  benzin  and  a  drop  or  two  of  sulphuric  ether ; 
pour  the  whole  into  half  a  pint  of  alcohol  and  wash  the  sur- 
face of  the  mold  with  this  mixture  twice,  allowing  it  to  dry 
after  each  application.  The  silver  solution  is  made  by  dissolv- 
ing one  dram  twenty  grains  of  nitrate  of  silver  in  a  mixture  of 
half  a  pint  of  alcohol  and  one  dram  of  acetic  acid.  The  mold 
is  floated  once  with  this  solution  and  allowed  to  dry  spon- 
taneously. Another  and  simpler  method  of  rendering  the 
mold  conductive  is  described  as  follows :  Dissolve  phosphorus 
in  pure  alcohol  until  a  strong  solution  is  obtained,  and  wash 
the  mold  with  this  mixture.  The  silver  solution  is  prepared 
by  dissolving  nitrate  of  silver  in  ammonia  to  saturation.  It 
is  to  be  poured  evenly  over  the  mold  and  allowed  to  float  over 
it  for  a  few  minutes.  The  solution  is  then  poured  off  and 
the  mold  allowed  to  become  partly  dry,  when  the  operation  is 


210  ELECTROTYPING. 

repeated.     Spots  which  do   not  appear  to  take  the  solution 
readily  should  be  wetted  with  it  by  means  of  a  soft  brush. 

WAX  SHAVERS,  VALUE  OF.— Most  large  electrotype 
foundries  are  equipped  with  wax-shaving  machines.  They  are 
chiefly  valuable  when  used  in  connection  with  power  molding 
presses  which  are  provided  with  indicators  to  register  the 
depth  of  impression.  The  shaved  case  being  of  uniform  thick- 
ness, and  the  proper  depth  of  impression  having  been  estab- 
lished and  noted  on  the  indicator,  the  operator  may  thereafter 
be  guided  entirely  by  the  indicator,  for,  if  the  press  is  stopped 
each  time  at  the  same  reading,  the  impressions  will  obviously 
be  all  of  the  same  depth.  A  shaved  case  is  also  preferable, 
because  the  "  skin "  is  thereby  removed  from  the  case,  and, 
with  it,  all  dust  or  dirt  which  may  have  collected  thereon,  or 
which,  being  in  the  wax,  may  have  risen  to  the  surface  when 
poured  in  the  case. 

WOODCUTS,  TO  PRESERVE.—  If  wood  is  wet,  oil  can 
not  enter  it ;  if  wood  is  oiled,  water  can  not  get  in.  As  it  is 
alternate  cold  or  dampness  and  heat  or  dryness  that  swell  and 
warp  cuts  and  blocks,  let  every  cut  you  care  anything  about 
be  soaked  in  oil  at  the  bottom  —  the  place  most  affected  —  and 
the  trouble  will  be  overcome.  You  can  then  lay  the  cuts  on 
cold  stones  or  presses,  or  in  moderately  warm  places,  with 
little  or  no  risk  of  injury. 

WOOD  ENGRAVINGS,  CLOSING  CHECKS  IN.— 
Wood  engravings,  when  subject  to  changes  of  temperature  or 
atmospheric  conditions,  sometimes  check  or  crack.  When  it  is 
desired  to  make  an  electrotype  of  such  an  engraving,  the 
checks,  if  not  too  large,  may  be  closed  by  covering  them  with 
strips  of  damp  blotting  paper  and  then  applying  a  hot  building 
iron  to  the  paper  until  it  is  wholly  or  partially  dry.  When  the 
check  has  been  closed,  the  mold  should  be  made  at  once,  before 
it  has  time  to  open  again. 


INDEX. 


Acid,  to  ascertain  percentage  in  solu- 
tion, i6i;  effect  of,  on  nickel  bath, 
i6i;  effect  of  acid  in  solution,  i6i; 
hydrochloric,  i6i;  muriatic,  i6i; 
sulphuric,  i6i;  soldering,  162;  acid 
gauge,   58 

Adams,  J.  A.,  8,  16 

Agitation  of  bath  advisable,  51 ;  bene- 
fits of,  162;   methods  of,  164 

Alkalinity  and  acidity,  165 

Alloy,  fusible,  165 

Amalgamation  of  zinc,  165 

Ammeter,  60,  165 

Ammonia,  166 

Ampere,  166 

Air  blast  for  blackleading,  86 

Albert,  Doctor,  69 

Anchoring  plates,  146,  166 

Anode,  166;  connections,  167;  hooks, 
167;    plates,  167 

Antimony,  167 

Backer-up,  the,  167;  backing  up 
press,  168 

Backing  metal,  107 

Backing  pan,  107 

Baths,  constituents  of,  35;  size  of 
depositing  vat,  39;  testing  the 
solution,  40;  steel,  brass  and  nickel 
baths,  41,  44;  brassing  solution, 
43;  management  of  bath,  46;  holes 
in  shells,  48;  temperature  of  bath, 
48;  cyanide,  49;  agitation  of  bath, 
51;  Englehard  process,  52;  Dun- 
ton  method,  54;  Leetham  appa- 
ratus, 55 

Battery,  Smee,  15,  20;  strength  of, 
18;  scientific  knowledge  not  essen- 
tial, 19;  positive  and  negative 
plates,  20;  positive  and  negative 
poles,  20;  electrode,  anode,  cath- 
ode, volt,  ampere,  watt,  20;  platin- 
izing, 22;    care  of  battery,  24 


Beginning  a  job,  63 

Beveling  machine,  134 

Black  electrotypes,  174 

Blackleading,  16,  84,  168,  169 

Blister  on  shells,  169 

Blistered  molds,  191 

Blocking,  sectional  and  wood  blocks, 
143;  rotary  planer,  145;  anchor- 
ing and  nailing,  146,  166;  warp- 
ing, 147;    dovetailing,  147 

Blowpipe,  138 

Blue  vitriol,  35 

Body  mold,  113 

Book  plates,  135,  136;  device  for 
holding,  170 

Brass  bath,  41,  44 

Brassplating,  170 

Brittle  deposit,  171 

Bronzing  solution,  171 

Brushes,  cleaning,  173 

Building,  wax  knife  and  how  to  use 
it>  79  i  how  to  use  building  iron, 
80;  making  electrical  connection 
with  mold,  8i 

Burning,  172 

Cases,  warming  of,  172;  handling  the 
case,  81;    thickness  of,    72. 

Casting,  the  furnace,  105;  leveling 
stand,  1 06;  backing  pan,  107;  com- 
position of  backing  metal,  107; 
preparing  the  shell  for  backing, 
108;  flattening  plates,  no;  electro- 
typer's  press,  no;  casting  hard 
shells,  172;  mounting,  112;  metal 
bases,  11.2;  body  mold,  113;  cool- 
ing the  cast,  114;    saw  table,  116 

Cathode,  172 

Circuit,  172 

Cleaning,  brushes,  173;  cuts,  173; 
electrotype  casts,  173;  plate  ma- 
chine, 173 


211 


212 


INDEX. 


Coating  molds,  191;  coating  of  cop- 
per, preliminary,  90 

Coloring  electrotype  medallions,  174 

Color  plates,  registering,  174 

Combination  blacklcading  machine,  87 

Composition,  molding,  67 

Concave,  174 

Conductors,  quantity  of  current,  95; 
size  of  rods,  96;  importance  of 
good  connections,  97 

Conductivity,  175;  of  mold,  90,  91, 
92;  of  solution,  202 

Connections,  175;  importance  of  good 
connections,  97 

Copper,  dissolved  by  solution,  176; 
scraps  utilized,  176;  to  separate 
copper  from  water,  176;  weight  of 
copper,  177;  how  to  assay  copper 
solution,  203;  copper  sulphate,  35; 
copper  vat,  38 

Coppering  foliage  and  plants,  92 

Corrections,  see  Rezising 

Corrosion  of  copper-faced  type,  177; 
to  prevent  corrosion,  177 

Coulomb,   178 

Cost  of  shells,  177 

Crocus,  178 

Current,  high  tension,  178;  strength, 
178;  measuring,  178;  restricting 
action  of,  89 

Curved  electrotypes,  casting,  179;  ex- 
pansion of  curved  plates,  179 

Cutters,  130 

Cyanide  of  potassium,  49 

Davis,  Daniel,  10,  13 

Davis'  Manual  of  Magnetism,  13 

Deposition,  rate  of,  28,  180;  econom- 
ical deposition,  180 

Deposit,  cost  per  foot,  25 

Depositing,  vat,  38,  39;  striking  the 
mold,  99;  holes  in  shell,  48,  100; 
causes  of  imperfections,  loi;  time 
required  to  deposit,  102 

Discovery  of  electrotyping,  7,  8 

Doctor  Albert  process,  69 

Dovetailing,  147 

Dunton's  hot  box,  186 

Dunton  method,  54 

Durability  of  electrotype  plates,  180 

Dynamo,  choosing  a,  30,  180;  superior 
to  battery,  25  ;  capacity  of, '27;  con- 
nections, 28;  rate  of  deposition,  28, 
29;  care  of,  33;  current  for  nickel- 
facing,  34 

Electrical  connections  with  molds,  82 
Electrical  terms,  meaning  of,  20 
Electromotive  force,   181 
Electrotyping  in  America,  181 
Elkington  &  Company,  8 
Englehard  process,  52 


Filtner,  William,  8,  :6 

Finishing,  tools  required,  119;  rough 
finishing,  119;  low  spots  in  plate, 
122;  straightening,  123;  finishing 
half-tones,  181,  182;  standard  thick- 
ness of  plate,  123;  shaving  machine, 
123 

Forms,  preparation  of,  64 

Furnace,  105 

Glass  rails   for  vats,   207;     Silvering 

solution  for  glass,  202 
Goose-bill,  see  Cutters 
Graphite  in  metallizing,  83 
Gutta-percha  molds,  182 

Hard  shells,  casting,  172 

Half-tones,  and  electrotypes,  184;  in- 
serted in  electrotype  plates,  184; 
molding  of,  185 

Holes  in  shells,  48,  100,  185 

Horse-power,  186 

Hot  box,  Dunton's,  186 

Hot  solution,  remedy  for,  204 

Hydrometer,  58 

Impression,  depth  of,  71,  72;  taking 
the  impression,  74 

Instruments,  measuring,  58,  188;  acid 
gauge,  58;  voltmeter  and  amme- 
ter, 60;  switchboard,  61 

Inventions  in  electrotyping,  187 

Iron,  deposition  of,  187 

Irregular  shaped  objects,  electrotyp- 
ing of,  90 

Jacobi,  Professor,  7 
Jordan,  C.  J.,  7 

Knight,  Silas  P.,  16,  86 

Leetham  apparatus,  55 

Leveling  stand,  106;   leveling,  187 

Line  gauge,  137 

Lineholder,  129 

Litmus  paper,  188 

Low  spots  in  plate,  how  to  detect,  122 

Massachusetts  Charitable  Mechanic 
Association,  1 1 

Measuring  instruments,  see  Instru- 
ments 

Medallions,  coloring,  174 

Melting  point  of  metals,  188 

Metal  bases,  112;  metal  molds.  Dr. 
Albert's,  150;  electrotype  metal, 
188;  capacity  of  metal  pots,  189; 
specific  gravity  of  metals,  189 

Metallizing,  use  of  graphite,  83 ;  black- 
leading,  84;  wet  process,  86;  air 
blast,  86;  restricting  action  of  cur- 
rent,   89;     preliminary    coating  of 


INDEX. 


213 


copper,  90;  irregular  shaped  ob- 
jects, 91;  conductivity  of  mold, 
90,  91,  92;  coppering  flowers  and 
leaves,  92 

Molding,  press,  71,  75,  76,  190;  im- 
provements in,  16;  composition,  67, 
189,  190;  blistered  molds,  191; 
metallizing  molds,  209;  striking  the 
mold,  99;  gutta-percha  molds,  182; 
Dr.  Albert  process,  69;  preparation 
of  mold,  69,  70;  cooling  cases,  70; 
depth  of  impression,  72;  even 
thickness  of  cases,  72;  warming 
cases,  73 ;  wax  kettle  and  table,  73 ; 
taking  the  impression,  74 

Molding  wax,  to  soften,  191 

Mounting,  112,  146 

Murray,  Joseph,  9 

New  method  of  making  electrotypes, 

181 
Nickel-facing,  34,  192 
Nickel  electrotypes,  191 
Nickel  solution,  193 
Nickeltypes,  194 
Nickel  bath,  41 

Ozo  compound,  196 

Ozokerite,  67;  to  soften  or  harden,  196 

Patina,  imitation  of,  196 

Peeling,  to  prevent,  197 

Pinholes,  197 

Planer,  rotary,  for  blocks,  145 

Plants  and  flowers,  coppering,  92 

Plates,  apparatus  for  flattening,  1 10 

Plating  without  a  battery,  197 

Platinizing,  21 

Postage  stamp  plates,  198 

Preparation  of  work,  63 ;  shaving  and 
underlaying  cuts,  64;  wood  cuts, 
64;    forms  to  have  bearers,  65 

Press,  electrotyper's,  no 

Punches,  revising,  138 

Rapid  electrotyping,  198 

Reference  list  of  terms,  etc.,  161 

Resistance,  198;  resistance  board,  61, 
199 

Reverse  electrotyping,  199 

Revising,  tools,  136;  revising  stick, 
'37;  punch,  138;  line  gauge,  1^7; 
blowpipe,  138;  method  of  inserting 
corrections,  138,  139,  140;  brass 
standards,  140;  type  high  stand- 
ards, 142 

Rough  finishing,  119 

Router,  131 

Routing,  see  Trimming  and  Routing 


Salary,  foreman's,  182 

Sawing,  etc.,  115,  118 

Saws,  care  of,  199 

Sectional  blocks,  143 

Series,  electrotyping  in,  200 

Shaving  machines,  123 

Shavers,  wax,  210 

Shell,  preparing  for  backing,  108; 
holes  in,  48,  100,  185;  time  re- 
quired to  deposit,  102;  washing 
shells,  207;  wrinkles  in,  208;  cost 
of  shells,  177 

Shootboard,  127 

Silver  electrotyping,  201 

Silvering  solution  for  glass,  202 

Sink,  104 

Smee  battery,  15,  21 

Solution,  hot,  remedy  for,  204;  sil- 
vering, for  glass,  202;  specific 
gravity  of,  205;  how  to  assay  cop- 
per solution,  203;  conductivity  of 
solution,  202;  testing  the  solution, 
40. 

Specific  gravity,  of  solutions,  205; 
how  to  find,  59 

Spencer,  Thomas,   7 

Standards,  brass,  140 

Statistics,  205 

Steel  bath,  41 

Stick,  revising,  137 

Sulphuric  acid,  35,  161 

Sweating,  206 

Switchboard,  61 

Temperature  of  bath,  48 

Thickness  of  plate,  123 

Three-color  blocks,  electrotypes  of, 
206 

Tools  for  finishing,  119;   revising,  136 

Trimming  and  routing,  127;  shoot- 
board,  127;  the  lineholder,  129; 
cutters,  130;  the  router,  131;  book 
plates,   134;    beveling  machine,  134 

Type  high  standards,  142 

Vats,  glass  rails  for,  207 
Verdigris,  to  remove,  207 
Voltmeter  and  ammeter,  60,  165 

Warping  blocks,  147 

Washing  shells,  207 

Watt,  208 

Wax  shavers,   210;    wax  kettles,  73, 

209;    wax  molds,  metallizing,  200; 

wax  engraving,  208;    wax  knife,  its 

use,  79;    wax  table,  73 
Wet  process  of  blackleading,  86 
Wilcox,  J.  W.,  10 
Woodcuts,  64;    to  preserve,  210 
Wrinkles  in  shells,  208 


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Lessons  on  Decorative  Design  —  Frank  G.  Jackson 2.10 

Lessons  on  Form  —  A.  Blunck 3.15 

Letters  and  Lettering  —  Frank  Chouteau  Brown 2.10 

Lettering  for  Printers  and  Designers  —  Thomas  Wood  Stevens 1.00 

Line  and  Form  —  Walter  Crane 2.10 

The  Principles  of  Design  —  E.  A.  Batchelder 3.00 

Theory  and  Practice  of  Design  —  Frank  G.  Jackson 2.60 

ELECTROTYPING  AND  STEREOTYPING 

Electrotypinq  —  C.  S.  Partridge.     Being  revised. 
Partridge's  Reference  Handbook  of  Electrotypinq  and  Stereotyp- 
ing—  C.  S.  Partridge $1.50 

Stereotyping  —  C.  S.  Partridge.     Being  revised. 

ESTIMATING  AND  ACCOUNTING 

A    Money-making   System    foe   the   EmpIiOying   Printer  —  Eden   B. 

Stuart $1.00 

Actual  Costs  in  Printing  —  Isaac  H.  Blanchard 5.00 

Style  2.  Annual  Tables  for  Printers  and  Binders.  Every  practical 
printer  insists  on  revising  his  cost  figures  each  year,  and  for  that 
purpose  the  cost-figfuring  tables,  together  with  the  blank  sheets  for 
use   in   annual   inventory,    have  been    bound   togetlier  in  convenient 

book   form    2.00 

Campsie's  Pocket  Estimate  Book  —  John  W.  Campsie 75 

Challen's  Labor-saving  Records  —  Advertising,  Subscription,  Job  Print- 
ers. 50  pages,  flexible  binding,  $1 ;  100  pages,  half  roan,  cloth  sides, 
$2,  and  $1  extra  for  each  additional  100  pages. 

Cost  of  Printing  —  F.  W.  Baltes 1.50 

Employing   Printer's   Price-list  —  David   Rainaley 1.25 

Fundamental  Principles  of  Ascertaining  Cost  of  Manufacturing  — 

J.   Cliff  Dando   10.00 

Hint  for  Young  Printers  Under  Eighty  —  W.  A.  Willard 50 

How  to  Make  Money  in  the  Printing  Business  —  Paul  Nathan 3.20 

Nichols'  Perfect  Order  and  Record  Book 3.00 

Order  Book  and  Record  of  Cost  —  H.  G.  Bishop 3.00 

Printer's    Insurance    Protective    Inventory    System  —  Charles    S. 

Brown 10 .  00 

Starting  a  Printing-office  —  R.  C.  Mallette 1.60 

LITHOGRAPHY 

Album  Lithographique  (specimens)    $1.50 

Handbook  of  Lithography  —  David  Cumming 2.10 

Lithographic  Specimens   3.50 

Photo-lithography  —  George  Fritz 1.85 

Practical  Lithography  • —  Alfred  Seymour   2.60 

The  Grammar  of  Lithography  —  W.  D.  Richmond 2.10 

MACHINE  COMPOSITION 

A  Pocket  Companion  for  Linotype  Operators  and  Machinists  —  S. 

Sandison     $1 .  00 

Correct  Keyboard  Fingbeino  —  John  S.  Thompson 25 

Facsimile  Linotype  Keyboards 25 

History  of  Composing  Machines  —  John  S.  Thompson 2.00 

Thaler  Linotype  Kbyboaed 4 .  00 

The  Linotype  Operator's  Companion  —  E.  J.  Barclay 1 .00 

Thb  Mechanism  of  this  Linotype  —  John  S.  Thompson 2.00 


MISCELLANEOUS 

A  Treatise  on  Photooravuhb  —  Herbert  Deniston $2.25 

The  Art  of  Engraving 1 .  60 

Author  and  Printer  —  F.  Howard  Collins 2.35 

The  Building  of  a  Book  —  Frederick  H.  Hitchcock 2.20 

Eight-hour-day   Wage   Scale  ^  Arthur   Duff 3.00 

The  Graphic  Arts  and  Crafts  Year-book,  $5.00;    foreign 5.80 

Inks,  Their  Composition  and  Manufacture  —  C.  Ainsworth  Mitchell 

and  T.  C.    Hepworth 2.60 

Manufacture  ok  Ink  —  Siginund  Lehner   2.10 

Miller's  Guide  —  John  T.   Miller 1 .  00 

Oil  Colors  and  Printing   Inks  —  L.  E.  Endes 2.60 

Practical    Papermaking  —  George   Clapperton 2.60 

Printer's  Handbook  of  Trade  Recipes  —  Charles  Thomas  Jacobi....   1.85 
Writing  for  the  Press  —  Robert  Luce 1.10 

NEWSPAPER  WORK 

Establishing  a  Newspaper  —  O.  F.  Byxbee $   .50 

Gaining  a  Circulation  —  Charles  M.  Krebs 50 

Perfection  Advertising  Records 3.50 

Practical  Journalism  —  Edwin  L.  Shuman 1.35 

PRESSWORK 

A  Concise  Manual  of  Platen  Presswork  —  F.  \V.  Thomas $   .25 

Color  Printer  — •  John  F.  Earhart. 

The  Harmonizer  —  John   F.   Earhart 3.50 

Tympan    Gauge   Square 25 

Overlay  Knife    25 

Practical  Guide  to  Embossing  and  Die  Stamping 1.50 

Stewart's  Embossing  Board,  per  dozen 1.00 

PROCESS  ENGRAVING 

Penrose's  Process  Year-book,  1906-7 $2.85 

Photoengraving  —  H.  Jenkins;    revised  and  enlarged  by  N.  S.  Amstutz  3.00 

Photoengraving  —  Carl  Schraubstadter,  Jr 3 .  00 

Photo-mechanical  Processes  —  W.  T.  Wilkinson 2.10 

Photo-trichromatic    Printing  —  C.    G.  Zander 1.50 

Prior's  Automatic  Photo  Scale 2.00 

Reducing    Glasses    35 

Three-color  Photography  —  Arthur  Freiherrn  von  Hubl 3.50 

PROOFREADING 

BiGELow's  Handbook  of  Punctuation  —  Marshall  T.  Bigelow $   .55 

Culinary  French    35 

English  Compound  Words  and  Phrases  —  F.  Horace  Teall 2.60 

Grammar  Without  a  Master  —  William  Cobbett 1.10 

The  Orthoepist  —  Alfred   Ayres 1 .  35 

Webster's    Pocket    Dictionary 50 

Pens  and  Types  — •  Benjamin  Drew 1.35 

Proofreading  and  Punctuation  —  Adele  Millicent  Smith 1.10 

Punctuation  —  F.    Horace   Teall 1.10 

Stylebook  op  the  Chicago  Society  of  Proofreaders 30 

The  Art  op  Writing  English  —  J.  M.  D.  Meiklejohn,  M.A 1.60 

The   Verbalist  —  Alfred   Ayres 1.35 

Typographic  Stylebook  —  W.  B.  McDerniutt 50 

AVilson's  Treatise  on  Punctuation  — •  John  Wilson 1.10 


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